The practice of blended learning needs to be guided by blended learning theories and other related theories. The emergence and development of blended learning is the product of learning psychology and pedagogy in the information age. Therefore, the implementation of blended learning needs to be guided by systems theories, educational communication theories, learning theories, teaching theories, and curriculum theories. Certain learning modes, as well as related design and practice models, have emerged from blended learning research and practice. In this chapter, Sect. 1.1 briefly reviews the connotation and development of blended learning; Sect. 1.2 introduces the theoretical basis for the emergence and development of blended learning, pointing out that the increasing prevalence of blended learning is based on the development of teaching and learning in the information age; Sect. 1.3 explains the theoretical basis of blended learning and its guiding role for blended learning; Sect. 1.4 introduces several modes of blended learning and describes how these modes can seamlessly connect online and offline learning; Sect. 1.5 introduces the design models and implementation models of blended learning. As a systematic summary of relevant theories and research on blended learning, this chapter shows the connotations and characteristics of the theories and highlights their guiding significance and value for blended learning. This chapter can be used as a reference by teachers, instructional designers, educational technology personnel, educational administrators, and researchers.

1.1 The Concept of Blended Learning

Blended learning was first introduced in the field of corporate human resources training, aiming to overcome the limitations of time and space in face-to-face teaching, including small class size, poor timeliness, and high training cost. Since the 1960s, some large international companies, such as IBM and Boeing, have attempted to make it possible to train hundreds or even thousands of employees at the same time with the support of communication technology. Communication technology has been developing rapidly, evolving from the original mainframe computers and minicomputers to television media in the 1970s, CD-ROMs in the 1980s, and to various communication methods based on the Internet in this century. No matter how the technology has changed, the purpose of blended learning in corporations remains the same, that is to overcome the human resource constraints and maximize training effectiveness (Bersin 2004). The face-to-face learning component plays a vital role in training work skills and the inheritance of corporate culture. Therefore, integration of the technology-based learning mode and the advantages of the face-to-face mode has been adopted by corporate human resources training.

In the 1990s, Internet-based E-Learning had gradually become popular with the development of information technology. Due to the differences in the media, the approaches, and the target audience’s needs between face-to-face learning and E-Learning, the two learning methods, to a large extent, were separated during that period. The E-Learning mode provided learners with a richer technical environment and a more convenient way to obtain resources. However, the E-Learning mode also had some disadvantages, such as low engagement and a poor real-time interactive experience. It is recognized that students have difficulties in completing learning tasks independently in the unsupervised network environment. As a result, a more effective and flexible blended learning method has been applied in teaching and learning by education researchers and practitioners. “Blended learning” has been proposed as a proper term. Initially, blended learning was considered as a simple combination of E-Learning and face-to-face learning, as moving classroom teaching to the Internet via information technology, or as supplementary extra-curricular learning tasks. Perceptions about blended learning have gradually changed; now it is seen as a learning mode that can improve classroom learning. An increasing number of researchers have begun to realize that the word “blended” should be considered as “integration” and “fusion”, instead of simply referring to “combination”. Blended learning is not limited to merely integrating face-to-face and online learning environments, but is a systematic reconstruction of multiple elements including learning resources, teaching strategies, learning environments, learning tools, and teaching and learning models.

From a historical perspective, as a social activity, education is certainly affected by social productivity, particularly technological advancement. Communication technology is the most important technology that affects education. Its development has revolutionized education. In primitive society, education was combined with life and labor without the distinction between formal and informal. Body language, as the dominant means of communication, aimed to maintain livelihoods. In an agricultural society, the dominant communication means used in education were word of mouth and hand-compiled books. Due to different needs in the society, formal and informal education was distinguished. Formal education was mainly in government and private schools, where teaching was conducted in either a centralized or a decentralized manner. Moreover, personalized learning was adopted without distinction among classes and school years. Informal education referred to the development of labor skills by using scenario-based learning for agriculture, and apprenticeship, etc. In industrialized society, word-of-mouth as the means of communication was adopted in education, though the bulk-printing of books and basic computer technology were also included. Due to the need for a large amount of standardized manpower, formal education shifted from the elite to the public, with classroom teaching as the main teaching mode. As a result, standardization and large-scale education came into being, such as schools, school years, curriculum, and courses. At the same time, the focus of informal education changed from labor skills in agricultural society to work skills, while the teaching strategy changed from scenario-based learning for agriculture to factory apprenticeship.

In the information society, information and communication technology are the foundation of the society; information resources are the major development resources; and digital industries are the leading field in the society. Information, together with matter and energy, constitutes the three key indispensable resources. Multimedia technology and Internet technology are widely integrated in education. Formal education has changed from popularization in industrial society to universalization in the digital society. In addition, with the learner-centered perspective, formal education has maintained its scalability and added the personalization. The teaching strategy has changed from face-to-face classroom teaching in the industrial society to the integration of scheduled face-to-face learning and flexible technology-enabled learning, such as a hybrid form that merges physical space and virtual cyberspace. With the development of emerging information technologies, such as cloud computing, Internet of Things, artificial intelligence, and biological computer technology, physical space and virtual cyberspace will be integrated more deeply. As a result, education has the potential to satisfy the learning need for everyone and can happen anytime and anywhere, allowing the seamless integration between formal and informal education, supporting personalized and lifelong learning. In this way, learning can move towards a new ecology of ubiquitous learning.

1.2 The Rationale for the Emergence and Development of Blended Learning

Blended learning is a learning mode that integrates face-to-face learning and technology-enabled learning. In order to achieve optimal learning effect under specific conditions, blended learning reconstructs the core elements of education, including goals, content (resources), media, methods, evaluation, and teaching teams, based on the nature of education, the laws of education and learning, and required future manpower. As a product of societal, economic, and technological development, it is certain that blended learning will become the new norm of education. Blended learning can not only meet the needs of societal development for education, but also meet the requirements of individual development. The emergence and development of blended learning has a solid theoretical foundation in psychology and pedagogy.

1.2.1 Psychological Rationale

Blended learning attends to both the commonality and individuality of students

Psychological research points out that people have common and individual traits, some highly relevant to teaching, while some not very relevant. Within the common and individual traits related to student learning, those that are not related to the content of a particular discipline are commonly referred to as common traits and individual traits of student learning in psychology.

The fact that students have learning-related common traits provides foundations for face-to-face teaching and online synchronous teaching, while students’ learning-related individual traits demonstrates the role that E-Learning can play. Therefore, the emergence and development of blended learning is historically inevitable. In the following part, the common features, and individual characteristics of student learning in a general sense will be briefly described so as to gain a clearer understanding of how to design good blended learning accordingly.

Characteristics of common traits

The psychological development of an individual is sequential and phased, therefore students in different age ranges will show corresponding and common general characteristics, including stage characteristics of cognitive development, psychosocial development, and moral development.

Concerning the characteristics of cognitive development, the well-known psychologist Jean Piaget proposed the four Piagetian stages of cognitive development, namely Sensorimotor Stage (0–2 years old), Preoperational Stage (2–7 years old), Concrete Operations Stage (7–11 years old), and Formal Operations Stage (11 years old and later). Identifying learner characteristics of cognitive development at each stage is the key foundation to instructional design.

Regarding the characteristics of psycho-social development, Erik H. Erikson developed his eight stages of personality development that integrate self-development and environmental influences (Erikson 1964). Trust and Mistrust (birth to 18 months): at this stage, children feel secure if they receive love and affection in a stable and predictable environment. This security allows them to trust others, otherwise babies will mistrust. Autonomy and Doubt (18 months to 3 years old): at this stage, children who are allowed freedom to explore, within limits, learn self-confidence, otherwise they may become discouraged and begin to feel worthless. Initiative and Guilt (3 to 6/7 years old): at this stage, children are bundles of energy, full of imagination and initiative. They begin to master peer relationships and language. If they are not encouraged to participate, they may feel guilty about the extent of their own ambitions and fail to develop the skills to play and work with others. Industry and Inferiority (6/7 to 12 years old): children at this stage begin to undertake some tasks independently and work together with others. If teachers can encourage and praise them, it is more likely that children will develop a sense of diligence and a proactive personality, otherwise, they are prone to develop a sense of inferiority. Identity and Identity Confusion (12 to 18 years old): children in this period start to develop self-identity. In other words, individuals try to establish a coherent sense of self (including his/her physical appearance, previous situations, status-quo, the limitations of environment and conditions, and the prospect of his/her future) as a whole. If children are provided with the right guidance from teachers and parents, they will successfully construct their self-identity, otherwise confusion of self-identity may appear. Intimacy and Isolation (18 to 30 years old): this period is the stage of love, marriage, and early family life. Youths seek to develop intimate personal relationships with others without losing their self-identity. If they fail to do that, they will develop a sense of loneliness. Generativity and Stagnation (30 to 60 years old): this is the challenge of the middle years of life. Raising children, creative activities, and community service are ways people give to others in this stage. Being unable to contribute in these ways can bring about boredom, restlessness, stagnation, and a feeling that life is meaningless. Integrity and Despair (after age 60): being able to look back on life with contentment and few regrets is the main task of Stage 8. Integrity involves having a good perspective on life in one’s final years. People who struggled through life without feeling a part of it may end up facing death in despair.

According to Erickson, there are corresponding key influencers in each of the above stages, namely: mother, father, family members, neighbors, as well as school teachers and students, peers and small group members, friends, colleagues, spouses, and the whole human race (Erikson 1964). Characteristics of psycho-social development influence the establishment of personality. How people interact with others and things affects the development of their personalities.

Regarding the characteristics of moral development, Lawrence Kohlberg proposed three moral levels and six stages of moral reasoning. The three levels are pre-conventional morality, conventional morality, and post-conventional morality. Each level has two stages. These stages can serve as reference for the development of students’ morality (Shaffer and Kipp 2012).

The characteristics of cognitive development affect the design of the difficulty level of learning objectives, the abstraction of the content, the format of learning resources, and the design of learning activities. The characteristics of psycho-social development may constrain the design of emotional interaction between teacher-student, student–student, teams, activities, as well as feedback and assessment; while the characteristics of moral development affect the design of learning activity guidelines.

In a society that promotes lifelong learning, learners can range from primary to middle school students, college students to the elderly. All learners have the above-mentioned characteristics of cognitive, psycho-social, and moral development related to learning as common features. For learners of the same age, such common features can serve as the basic guidelines for designing learning objectives, content, resources, activities, collaboration, interaction, feedback, and assessment in face-to-face or real-time online learning. Yet, for the learners of different age groups, self-paced online learning might work better. Therefore, it is necessary to develop blended learning.

Individual traits

Human development involves not only common features, but also individual characteristics. In other words, people have individual differences which are influenced by genetics, social living conditions, education, and other factors in their process of socialization. Some are related to learning, including differentiated traits like learning interests and learning styles.

Learning interest demonstrates learners’ willingness to learn. Psychologists divide learning interests into personal interests and situational interests. Personal interests are idiosyncratic and relatively stable, referring to a person’s tendency to pay attention to specific stimuli, objects, and topics. Situational interests, on the other hand, are responsive. When situational interests are “triggered”, they can attract learners’ attention in a short period of time. If situational interests are “maintained”, they can promote students to stay focused on the same task or topic over a long period of time (Ormrod 1999).

Generally, interests can facilitate information processing more efficiently (Ormrod 1999). In addition, to some extent, interests and learning mutually reinforce each other. When students experience a sense of competence, their learning interest may increase. Even if students are not initially interested in some learning content or an activity, they may develop an interest after experiencing success. Therefore, it is necessary to understand interests of learners, to trigger and maintain learners’ personal and situational interests, to have a variety of teaching modes, and an autonomous learning atmosphere. All of these key elements can be included in blended learning.

Learning style refers to the psychological characteristics indicating learners’ perception of stimuli and their responses to the stimuli. In other words, learners tend to choose special strategies in their learning process. The following section mainly discusses learners’ different needs for learning environments and their different cognitive styles.

Learners’ different needs for learning environments

Affective needs refer to learners’ need for encouragement and comfort in their learning process. Social needs refer to learners’ need for peer discussion. Environmental and emotional needs refer to learners’ preference towards environment and emotions when learning, such as studying in a quiet environment, having snacks when reading, walking back and forth when thinking, or having a certain efficient learning period.

Differences in cognitive styles

Cognitive style refers to the strategies learners are used to adopting when they perceive, recall, and reflect. It shows the individual differences of learners in the process of organizing and processing information and reflects the different characteristics of learners in perception, memory, reflection, and problem-solving abilities. Each learner can have a variety of cognitive styles at the same time and utilize different combinations of them in the process of learning. Mainly, four types of cognitive styles have an impact on instructional design: the preferred sensory channel for perceiving or receiving stimuli, field-independent and field-dependent, holistic and sequential, and reflective and impulsive.

The preferred sensory channel for perceiving or receiving stimuli refers to the sensory channels that learners prefer in learning, including visual, auditory, and tactile/ kinesthetic.

Field-dependent and field-independent. The concept of the field dependence–independence cognitive style emerged as a result of the work of Witkin. A relatively field-independent person is likely to overcome the organization of the field, or to restructure it, when presented with a field having a dominant organization, whereas the relatively field-dependent person tends to adhere to the organization of the field as given (Witkin et al. 1977). Witkin et al. (1977) claimed that field independent individuals rely on an internal frame of reference, while field dependent individuals rely on an external frame of reference. Whilst field dependent individuals have a preference to learn in groups and to interact frequently with one another as well as the teacher, field independent learners may respond better to more independent and more individualized approaches. Also, field independent learners are more likely to have self-defined goals and to respond to intrinsic reinforcement, whilst field dependent learners require more extrinsic reinforcement and more structured work by the teacher. Whereas the field independent learners prefer to structure their own learning and to develop their own learning strategies, field dependent learners may need more assistance in problem-solving strategies or more exact definitions of performance outcomes (Witkin et al. 1977). Field independent individuals are more capable of dealing with situations requiring impersonal analysis, whilst field dependent individuals are better equipped to deal with situations requiring social perceptiveness and interpersonal skills.

Holistic and sequential. When dealing with learning tasks, individuals have two tendencies: one is a holistic, hypothesis-oriented strategy, which deals with tasks as a whole and tests relatively more complex hypotheses at the same time; the other is a sequential, fact-oriented, step-by-step strategy, which tests only one limited hypothesis at a time. Holistic learners are good at solving problems from a comprehensive and holistic perspective. They prefer to grasp the overall situation, and then find a breakthrough to solve problems, or solve complex problems first. They have high intuition and ambiguity, but low accuracy and profundity. In contrast, sequential learners use the “operational” method to learn. They are used to dividing problems into details to understand them and solving problems step by step, according to a logical sequence. They are also good at discovering the differences between different entities.

Reflective and impulsive. The concept was originally introduced by Kagan et al. (1964) to describe the individual differences in the speed with which decisions are made under conditions of uncertainty to employ impulsive or reflective cognitive tempos.

Impulsive children respond quickly with short latencies and numerous errors, while reflective children tend to inhibit their initial responses and to reflect upon the correctness of their responses, thereby exhibiting longer latencies and fewer errors.

Reflective children tend to analyze stimuli and organize them into detail components and, accordingly, perform better on tasks requiring attention to details. Impulsive children, on the other hand, tend to focus more on the stimulus as a whole and thus perform better on tasks requiring a more global analysis.

Since different learning activities require different psychological characteristics, it can only be said that a certain tendency is more suitable for a certain learning context, rather than that a learner with a certain tendency is necessarily smarter than one with another tendency.

In a relatively flexible and autonomous learning mode, blended learning can provide students with more choices in terms of the learning environment and learning partners, giving feedback via the system, resources via various media (such as visual, audio and text media), and allowing students to follow at their own pace. Thus, blended learning can meet the needs of students with different learning styles.

Blended learning provides personalized learning paths or pacing for students with different potential. The previous subsection discussed the common features and individual characteristics related to learning in general. To account for these characteristics simultaneously, a flexible learning mode like blended learning is needed and will become more prevalent. In fact, in psychology, some individual characteristics of learners, such as the disciplinary learning potential, learning needs, and learning competence of different students, are closely related to subject learning, but are difficult to be taken into consideration by face-to-face teaching alone; thus they would benefit from online teaching.

Multiple intelligence structure

Howard Gardner, a professor of psychology at Harvard University, proposed the Multiple Intelligences Theory after years of research. He defined intelligence as a “biopsychological potential to process information that can be activated in a cultural setting to solve problems or create products that are of value in a culture”. On this basis, he proposed nine different types of intelligence, namely, linguistic intelligence, logical/mathematical intelligence, spatial intelligence, bodily-kinesthetic intelligence, musical intelligence, interpersonal intelligence, naturalist intelligence, intrapersonal intelligence, and existential intelligence. Everyone was born with more than eight types of intelligence that are both independent and interrelated and has different strengths and weaknesses in intelligence. When solving problems and creating products, people combine and use these intelligences differently, which gives rise to each person’s different and individualized multiple intelligence structure. For students, each subject may tap multiple intelligences and involve their various combinations, which explains why they are talented and full of potential in one subject but lacking in potential in another subject.

Gardner’s “Multiple Intelligences Theory” helps educators to be aware of the multiple differences among students, and explains why some students can learn subjects they are good at easily and fast, but relatively hard and slowly when they learn the subjects that they are not good at. Online learning has the advantage to make full use of “multiple intelligences” to teach, to enable students to have their individualized learning paths, and to help students learn at their own pace (Zhang 2002).

Learning needs

Learning needs refer to the gap between what the learner wants to get out of the learning experience and their current state of learning and development. Due to learners’ differences in terms of their living environments, future jobs and positions, and their development potential, differences can be found in learners’ learning expectations.

Meanwhile, since the current learning levels of learners are also different, their learning needs vary too. Due to the large number of people in traditional classrooms, teaching is at the same pace and teachers cannot take into account the learning needs of different students. However, blended learning, which adopts a learning mode that combines “online and offline”, can expand the time and space of learning and thus meet the learning needs of different students. With a variety of learning resources, students can not only review and relearn, but also learn more content more deeply.

Learning competence

Learning competence refers to people’s ability to acquire knowledge, work on tasks, and seek development (Liu et al. 2018). Learning competence includes general abilities and specific abilities (Gao 1989; Zeng and Cao 2005). General ability is a comprehensive ability that is applicable to all or most studies. Although it is not discipline-specific, it has an impact on discipline learning and has the characteristics of transferability, universality, wide application, and stability. Yin and Bi (2000) categorized general learning abilities into basic abilities and comprehensive abilities, and proposed that the basic abilities of learners include observation ability, memory ability, thinking ability, and expression ability, while comprehensive abilities include self-learning ability, problem-solving ability, experimental ability, and creativity. It is also proposed that learners’ basic abilities and comprehensive abilities are cultivated through the learning of professional knowledge of a discipline, and can be applied to new learning, serving not only as the basis, but also the purpose of learning.

Special abilities are the abilities demonstrated in professional activities, such as disciplinary abilities. Lin (1997) believes that the intelligence and ability of learners should be organically combined with general abilities of the discipline, such as listening, speaking, reading, and writing in language subjects. The combination of discipline-related intelligence and competencies, strategies, and methods should also be included. Gardner’s (1993) multiple intelligence structure links disciplines to the intellectual structure of learners. He stated that everyone has a different match from the eight or nine types of intelligence, which explains why people perform differently in different subject areas.

There are differences in general learning abilities and the disciplinary competence of leaners, which directly affect the way, the efficiency, and the quality of their completion of disciplinary learning activities. Blended learning can not only provide a variety of learning paths and various learning support methods, but also enable learners to review, repeat, or learn more things, helping them to exercise and develop their own learning ability. Therefore, blended learning can resolve learners’ differences in learning ability and facilitate learners to better complete their learning tasks.

1.2.2 Pedagogical Rationale

Blended learning takes into account common features and individual characteristics of learners and enables learners with potential in different disciplines to learn through different learning paths at their own pace. Meanwhile, the information society requires education to promote the holistic and personalized development among students, which serves as an important pedagogical basis for the emergence and development of blended learning.

Blended learning realizes the essence of education—to promote “the development of each student”. Education is a social activity in which educators should have a positive impact on students. Having an accurate perspective on students is very important to systematically develop education. Likewise, such a perspective is crucial to realize the essence of education—“to promote the development of each student and improve the life quality and value of each one”. According to Gardner’s theory of multiple intelligences, although students’ intellectual structures vary, they all have unique potentials, which means that there are no students that cannot learn, only different students. At the same time, there are differences among students in terms of learning foundation, learning speed, learning interest, learning motivation, learning needs, and learning ability. Therefore, if schools can provide multiple development approaches for each student, it is possible to further develop each student’s superior intelligence, thus encouraging their learning motivation and facilitating the development of their weaker intelligence area to a certain extent. In this way, each student can enjoy a successful learning experience at school and contribute to the achievement of the educational purpose, which is to promote the development of every student.

Promoting the development of each student requires schools to carry out customized and individualized teaching and learning. Teaching and learning needs to be tailored to the unique needs of students. However, the realization of real personalized teaching and learning is a huge challenge for schools. It is not feasible to equip each student with a tutor, yet the development of technology enables the possibility to promote the personalized development of students. Learning analysis based on big data, adaptive systems, and Massive Open Online Courses (MOOC), has created conditions for providing students with suitable learning content and learning methods. “In the age of technology, people are more likely to pursue learning on their own and will not feel the sense of failure that comes when everyone is supposed to learn the same thing at the same time” (Collins and Halverson 2009, p. 110). Moreover, the development of information technology facilitates a variety of learning methods, from E-Learning to U-learning, which enable students to have more space to learn outside the classroom.

In recent years, scholars have examined how technology can facilitate personalized teaching and learning. For instance, Wei et al. (2019) identified seven behaviors of students in the classroom by using intelligent learning analysis technology, namely, listening to class, looking around, raising hands, sleeping, standing, reading, and writing. This technology can offer timely and accurate feedback on the learning of each student in the classroom, which can help teachers enhance teaching strategies, and optimize classroom learning and management. This will improve the efficiency of teaching and learning and contribute to the reform of personalized teaching and learning.

Since 2016, Tsinghua University has launched a smart teaching and learning tool—Rain Classroom. The tool covers every data collection session, from “before class” to “during class” to after class”. The back-end of the tool records detailed data of teaching and learning behavior, such as the number of students participating in the classroom, the timeslot that students enter the classroom, the slides they fail to understand, the questions that are answered incorrectly, the frequency that a preview video is watched before the class, and the completion and correct rate of the after-class homework. Such data can clearly restore most of the teaching and learning process in the real classroom. Using such data for data analysis and mining can support teachers to enhance the teaching process and help students to enhance the learning process. By adopting machine learning and artificial intelligence, the panoramic recording of big data will provide the foundation for teachers and students to make decisions in a scientific fashion, including individually analyzing past teaching and learning processes, objectively reflecting on the current teaching and learning situation, and proactively arranging future teaching and learning (Wang 2017).

Blended learning is one of the important approaches for schools to achieve student-centered personalized teaching and learning. On the one hand, blended learning allows teachers to implement various student-centered offline learning modes so that they can have interaction and communication with students. On the other hand, with the advantages of promoting personalized development among students, blended learning can take advantage of emerging technologies to break the limitations of time and space for providing students with personalized learning. By integrating online and offline learning, blended learning aims to “deliver ‘appropriate’ skills to ‘appropriate’ learners at ‘appropriate’ times by applying ‘appropriate’ learning techniques that fit ‘appropriate’ learning styles” (Singh and Reed 2001). In this way, learners will be able to have a personalized learning experience rather than learning in a one-size-fits-all classroom (Horn and Staker  2017).

Therefore, blended learning meets the essential requirements of education, follows the fundamental principles of education, and will become increasingly more common in education.

Blended learning helps to cultivate talents with twenty-first century core competences. So far, human beings have witnessed hunter-gatherer society, agricultural society, industrial society, and the move towards an information society (Toffler 1990). In the agricultural society, education was through apprenticeship or one-to-one tutoring, generally with only one room as the school building. In the industrial society, in order to meet the needs of large-scale teaching and learning, modern schools emerged and the education system transformed into “Factory Models of Schools” (Duan et al. 2009). In the twenty-first century, with the fast knowledge update and the diverse ways of knowledge acquisition, traditional teaching and learning are unable to adapt to the increasingly complex living and working environments. This is because society has put forward higher requirements for talents in terms of creativity, diversity, and individualization.

In the era of rapid change, the education field has been changing in order to cope with the development of the new era. Countries and international educational organizations have a common challenge to understand what kinds of talents to be trained for the new century. According to the Organization for Economic Cooperation and Development (OECD), the talents to be cultivated should have the following characteristics. The first is reflection, a relatively complex mental process including metacognition, creativity, and critical thinking. The second is the ability to cope with complex problems and unpredictable scenarios. According to the EU, the expectation is to cultivate talents with competences including critical thinking, problem-solving, teamwork, communication and negotiation skills, creativity, cross-cultural communication, and life-long learning (European Commission 2018). Regarding the development of core competences in Chinese students, it is expected that students will have six core competences, namely, humanity, scientific spirit, ability to learn, healthy life, responsibility, and innovation (Research Group on Core Literacy 2016).

By comparing the eight frameworks for core competences in the world, Dutch scholar Voogt and others came to the following conclusions: ① Four core competences are advocated by all the frameworks, namely collaboration, communication, ICT-related competences, and social and/or cultural awareness (including citizenship); ② The other four core competences advocated by most frameworks are creativity, critical thinking, problem-solving, and the capacity to develop high-quality products or productivity. These eight competences are the common pursuit of human beings in the information age and are called “the world common core competences” (Voogt and Roblin 2012). The above-mentioned competences can be further refined into the following four, namely, collaboration, communication, creativity, and critical thinking, which are the “twenty-first century 4Cs”. The world common core competences are the common pursuits of human development goals in the information age, which reflect educational trends in the world.

Blended learning has the advantages of offline, face-to-face classroom teaching and the advantages of online learning, such as various learning models, self-paced learning, idea sharing, resource sharing, and collaborative, inquiry-based problem solving. Blended learning can promote the development of students’ autonomous learning ability, identification ability, critical thinking skills, and creativity, which are the talents needed in an information society.

Researchers advocate that blended learning can contribute to the cultivation of twenty-first century core competences in students. Zhang et al. (2019) used the Wisdom Tree platform to establish a blended learning model based on the Small Private Online Course (SPOC), and found that students’ autonomous learning ability and learning efficiency were enhanced by adopting this model. Wang et al. (2018) conducted a survey on college students who participated in blended learning courses based on Massive Open Online Courses (MOOC). Their study found that this model improved students’ language expression, autonomy, and teamwork, strengthened the teacher-student and student–student communication, and thus improved learning effectiveness. These studies suggest that blended learning plays an important role in enhancing students’ problem-solving skills, teamwork, and other higher-order thinking skills.

Apparently, blended learning can help to cultivate talents with twenty-first century skills. To achieve this goal, blended learning needs to utilize the teacher-led and student-centered learning model to promote students’ autonomy and provide authentic problems to cultivate students’ problem solving skills. Also, blended learning needs to integrate the advantages of various teaching modes to provide students with appropriate learning paths and focus on collaborative learning to cultivate their collaboration and communication skills. Moreover, students should be offered a variety of learning tools and sufficient technical resources for self-paced learning so that students can become lifelong learners. The cultivation of students’ critical thinking and innovation skills should be integrated in the teaching and learning process. Nowadays, with rich online resources, students should be exposed to different ideas and be offered with more opportunities for hands-on practice and expression of their opinions with proper guidance.

All colleges and universities in China now consider blended learning as a development direction of educational reform. Colleges have started to use the established online resources, such as Chinese University MOOC, Chaoxing, and Zhihui Shu (Wisdom Tree) to support blended learning. More importantly, colleges need to choose or establish their own learning management systems, develop online resources, and implement multi-modal blended learning, so that blended learning can be widely adopted in all fields and disciplines of higher education, thus contributing to the reform of teaching and learning. The sixth part of this handbook provides helpful examples of blended learning in colleges and universities.

According to the theoretical foundations in psychology and pedagogy, blended learning should have face-to-face and online learning closely coordinated and seamlessly connected, considering the common features and the individual characteristics of students. Additionally, blended learning should respect the common development principles of learners at different stages and meet their individual learning needs. Therefore, blended learning requires a diversified design of learning activities and a hierarchical design of learning resources to allow different learning paces and paths, as well as personalized guidance for learners, according to their learning effectiveness, so that their learning potential can be fully developed. Meanwhile, blended learning can adopt more teaching strategies, such as independent learning, collaboration, and inquiry, to cultivate students’ core competences in the information age.

1.3 The Theoretical Basis of Blended Learning

To sum up, blended learning conforms to the laws of psychology, the nature of education, and its future trends. Blended learning is beneficial to cultivating individualized talents required by social development. The next question is how to design ideal blended learning. This section will illustrate the theoretical basis for identifying the ideal instructional design of blended learning, including systems theory, educational communication theory, learning and teaching theory, and curriculum theory.

1.3.1 Systems Theory and the Guidance for Blended Learning

Systems thinking was introduced by the Austrian American theoretical biologist, L. Von. Bertalanffy, in 1932. By using the concept of system as the focus, systems thinking explores the basic framework and methods that can tackle the complexity and dynamics of a system in a more appropriate and effective way. It emphasizes considering issues as a system. In other words, the components and the interrelationships and interactions among these components and their interactions with the environment should be considered, and the system should be processed as a whole to generate an overall effect of “1 + 1 > 2”.

The basic viewpoints of systems thinking are as follows: problems should be addressed as a whole; the emphasis is on the interconnection and interaction among systems, components and environments; the structure of the system is the internal basis for the system to maintain integrity and certain functionality; systems are hierarchical—a system itself is also a component part of a larger system, while a component is a subsystem made up of components of a lower layer; systems are dynamic, purposeful, and open; and exchange with the environment on matter, energy and information (Dou 1988).

Systems thinking is an important guiding ideology of blended learning. Blended learning considers online and offline learning as a whole. In other words, it is a process of design, development, implementation, evaluation, feedback, and refinement of online and offline learning. This process needs good planning and seamless connection between online and offline learning. Meanwhile, a good instructional design of blended learning requires systems thinking to involve the participation of several parties (such as content experts, technicians, graphic designers, instructional design experts, teachers, and students); the variety of teaching and learning modes and process (such as learning objectives, learning content, the composition of learners and their characteristics, online and offline learning activities, learning space, other teaching strategies, assessment and evaluation, teachers, learning support staff, the teaching and learning environment, and community). Moreover, the implementation of blended learning needs to consider learning support, online and offline learning activities, communication with peers and communities, the tracking of the learning process, and according personalized adjustment based on data analytics. In addition, the evaluation of blended learning needs to integrate online learning data and offline classroom performance to consider the relationship between students’ overall development and personality development. Several factors need to be balanced when focusing on learning outcomes and the learning process.

Systems Approach and the implications for blended learning

The scientific systems approach, or a systems approach, is a method according to the systematisms of things. It examines the research object as a whole with organization, structure, and function (Li et al. 2007). To be specific, it comprehensively examines research objects from the aspects of mutual relationship between the system and the components, between components and components, and between the system and the external environment. The general process of applying a systems approach to solve problems includes five basic steps: define the problem and set the goal, identify solutions, select the strategies, implement the solution, and evaluate the effectiveness. This problem-solving approach focuses on situational analysis and a holistic view, as well as relationship analysis. It is the general approach to support the whole process and the sub-processes of design, implementation, evaluation, feedback, and improvement in blended learning. Further, the application of the systems approach in blended learning can ensure optimal learning effectiveness.

The Theory of Complex Systems and the implications for blended learning

The Theory of Complex Systems is a series of theories about complex systems and is the further development of the Theory of General Systems. The Theory of General Systems refers to human-made established systems with central control mechanisms, stable structures, and predictable changes, while the Theory of Complex Systems focuses on complex systems without central control mechanisms and stable structures. Such systems are not designed, but evolve from the interactions between many dynamic components at the group level. The evolving process is a bottom-up process, as a self-organized process from messy to organized at the group level with numerous unpredictable possibilities. Along with the bottom-up process, the system will develop a top-down regulation process. Thus there is tension between the bottom-up process and the top-down process of the system. When this tension is directed toward adaptation to the environment, it not only generates many possible changes, but also filters the possibilities according to adaptability requirement, thus guiding the system to evolve and finally develop a system structure and operation mechanism that is adaptive to the environment.

In fact, teaching and learning is a complex system in itself. Blended learning is more complex than pure face-to-face or online learning. The goal of blended learning is to integrate the advantages of various teaching modes to achieve optimal learning effectiveness. How to integrate various teaching modes to develop an optimal teaching and learning system is particularly important because such teaching and learning systems include various elements, complex relationships, and unpredictable evolution processes. Students and teachers who pursue personalized teaching and learning play an active role. The required complex teaching system can be self-formed through the self-adaptation of the bottom-up generative process to the top-down environmental requirement and can result in the integration of various teaching modes. For blended learning, it is essential to provide teachers and students with freedom to choose teaching and learning modes independently so as to encourage their enthusiasm, but also to regulate the teaching and learning environment according to expected learning outcomes. By maintaining a reasonable tension, it is possible to integrate a variety of teaching modes and develop an optimal teaching and learning system, thus achieving optimal learning effectiveness.

1.3.2 Educational Communication Theory and Its Implications for Blended Learning

Educational communication is a communication activity between educators and learners in which educators select appropriate content according to the learning objectives and transmit knowledge, skills, ideas, and concepts to specific learners through effective media channels. The essence is to make communication and interaction more effective. Therefore, the theoretical framework of educational communication, which appeared before educational technology, can be used to interpret blended learning, as they both pursue the optimal effectiveness of teaching and learning interaction. With the development of psychology and the increasing recognition of constructivist epistemology, it is gradually realized that educational communication is a multi-directional interactive activity in which ideas and meanings are constructed by learners as subjects instead of being transmitted, thus adding new meaning to educational communication theories.

Communication channel selection and blended learning

Educational communication is a system mainly consisting of four components: educators, educational information, educational media, and learners. The four components interact and develop the following six relationships: educators and learners, educators and educational information, educators and educational media, learners and educational information, learners and educational media, and educational information and educational media (Nan and Li 2005). Dealing well with these six relationships is very important to ensure and improve the effectiveness of educational communication.

When educators and learners are identified in the system, the educational information will be provided accordingly. Among all the components, educational media is the most active and abundant, because most forms of media can store and transmit plenty of information, though the effectiveness of different communication channels may vary. This leads to the issue of the choice of communication channels, or even the simultaneous use of multiple channels. On the one hand, some specific content needs to use the most suitable transmission channel to achieve better communication effectiveness. On the other hand, according to constructivism and connectivism (see the Learning Theory section), there are meanings distributed across the connections among different nodes. For learners, they can adopt different educational media to gain information, support their scaffolding, and develop their own cognitive framework and understanding.

There are a variety of communication channels in blended learning that can meet different needs, including different subject matter, students’ learning styles, and students’ meaning construction, and thus enhance communication effectiveness. The relationship of educational media channels with educators, learners, and educational information respectively needs to be well aligned in order to achieve high-quality educational communication effectiveness.

Educational communication model and blended learning

The educational communication model is a theoretically simplified version that replicates the reality of educational communication. It briefly outlines the phenomenon of educational communication and the composition and relationship of various components in the process of educational communication. This model reveals the essential characteristics of educational communication.

The basic model of educational communication

The basic model of educational communication is developed according to the four components of the educational communication system and the important influences of feedback and environment on communication effectiveness. These four components are educators, educational information, educational media, and learners. This model reveals that the effectiveness of educational communication is the result of the interaction and interconnection of all components involved in the communication process instead of being determined by one component. Therefore, the various components in the communication process and the relationships among them should be considered in a holistic manner.

The typical model of educational communication

Based on the basic model of educational communication, whether educators and learners are physically together determines the development of a communication model of face-to-face education or distance education (Wei and Zhong 1992).

With the development of technology, the communication model of distance education based on the Internet has gradually become the mainstream. Information suppliers, i.e., information sources, are more diverse. It is more convenient to identify the characteristics of information recipients through big data. According to those relatively accurate data, information or content will be encoded more appropriately.

Means of transmission will be more abundant. Information recipients also have the right to choose. Given various decoding methods, and the different decoding of groups and individuals, interaction, communication and feedback can happen in a timely and multi-directional manner, making the meaning constructed by information recipients more diverse. Accordingly, the communication model of distance education based on the Internet is becoming increasingly diversified.

Blended learning involves face-to-face communication modes and distance, particularly Internet-based communication modes. Its communication processes, such as design, implementation, evaluation, feedback, and improvement, as well as functional elements, should not only follow the steps of these communication models and involve all elements, but also conform to all the principles of communication.

1.3.3 Learning Theories and Their Guidance on Blended Learning

Since the emergence of psychology in 1879, learning theories have gradually developed and resulted in many representative genres. Although the genres have distinctive viewpoints, all of them mainly explore three fundamental aspects: the essence of learning, the learning process, and the principles and conditions of learning (Chen and Liu 2019). An in-depth understanding of these theories and the application will help us fully understand the definition, nature, functions, and conditions of learning, thus providing a suitable theoretical basis for different blended learning scenarios.

Behaviorism and its applicable teaching scenarios

In the first half of the twentieth century, behaviorism became dominant in psychology. The core idea of behaviorism is that learning is the result of connections between stimuli and responses through repetitive attempts (Watson and Kimble 2017). If the desired response is reinforced in time, it is easier to develop stimulus–response connections and result in learning. The connections between stimuli and responses are emphasized by not only the classical conditioning theory by Ivan Pavlov and John Broadus Watson and the connectionism learning theory by Edward Thorndike, but also the operant conditioning theory by Burrhus Frederic Skinner. Later, some behaviorists began to absorb the ideas of the cognitive school and Albert Bandura’s social learning theory is an example. He believed that learning in essence refers to the process in which individuals obtain some new behavioral responses or amend existing behavioral responses by observing the behaviors of others and their reinforcement results.

Regarding the teaching content of each discipline, there is always something that does not require much thinking but needs to be remembered by students (such as English vocabulary, mathematical symbols, etc.), or something that has been approved by thinking but requires skilled memory and fast responses, or some motor skills. This is the teaching scenario where behaviorist learning theory can come into play. Behaviorism has been playing an important role in all teaching processes, including blended learning.

Cognitivism and its educational applications

In the 1960s and 1970s, behaviorist learning theories showed more and more limitations and could not explain how people learn through internal psychological mechanisms. More and more psychologists began to adopt a cognitivist approach, focusing on learners’ internal processing of knowledge. Based on behaviorist theories of stimulus–response connections, cognitivism emphasizes that the stimulus–response connections are resulted from the formation of cognitive structures, and claims that learning, in essence, is the process in which learners actively form cognitive structures in their minds through understanding. Cognitive learning theories mainly include Jerome Seymour Bruner’s discovery theory, David Ausubel’s assimilation theory, and Robert Mills Gagné’s information processing theory.

The philosophical basis of the cognitivist learning theory is objective epistemology, which recognizes the existence of objective truth or absolute knowledge. The theory determines that teaching, with students’ cognitive structure as the basis, is to persuade students to accept the newly taught knowledge and to incorporate it into their original knowledge structure, which then either expands or changes into a new one. This is how learning occurs.

Blended learning can take advantage of dual or multiple channels to gain a better understanding of students’ cognitive structures. It does so by adopting advanced learning analytics technology, such as big data or data mining, and analyzing the online learning trajectory of learners and the dialogue texts of activities, together with scales and questionnaires. This serves as the basis for the design of blended learning. At the same time, cognitivism emphasizes that learning is a meaningful process in which organisms actively form new cognitive structures. Therefore, the instructional plans of blended learning should be designed to meet the needs of different students so as to arouse students’ learning enthusiasm and enable them to internalize external objective stimuli into their internal cognitive structures through autonomous learning and teacher guidance. Cognitivism emphasizes the need to adopt flexible teaching procedures and instructional modes according to students’ age and experience as well as the nature of the discipline. Thus, in blended learning, appropriate arrangements should be based on learners’ mental development level and cognitive representation, so that they can make connections between their prior knowledge and experience and their new knowledge.

Learning perspective from constructivism and its applications to teaching

Constructivism is a further development of cognitivism and its essence is in direct contrast to the philosophical epistemology of objectivism. Specifically, extreme constructivist epistemology does not recognize the existence of objective truth, while moderate constructivist epistemology believes that the objective truth can be put aside first and the cognition of things is formed through the interaction of an individual’s prior experience with existing things. Different from the view of behaviorism and cognitivism, which regards learning as the individual activity of the learner, constructivism regards learning as a process in which an individual builds knowledge on prior understanding through interactions with social environments.

The pioneer of modern constructivism is Jean Piaget, who believed that knowledge neither comes from the subject nor the object but is constructed in the process of interaction between the subject and the object. The enrichment process of the cognitive structure of the organism is the process of the progressive construction of the cognitive structure of the subject from equilibrium to imbalance and back to equilibrium (Piaget 1997). Piaget’s view of cognitive learning is mainly to explain how to internalize the objective knowledge structure into a learner’s cognitive structure through their interaction with it (Piaget 1976). Therefore, his constructivist view belongs to cognitive constructivism.

As one of the representatives of social constructivism, Vygotsky emphasized the role of socio-cultural history in psychological development, especially the prominent position of activities and social interactions in the development of people’s higher psychological functions. He believed that higher psychological functions come from the internalization of external actions, which is achieved not only through teaching, but also through daily life, games, and labor (Vygotsky 1980). In addition, the inner intellectual action is also externalized into the external actual action, so that the subjective can be seen in the objective. The bridge between internalization and externalization is human activity.

Constructivists emphasize the dynamic nature of knowledge, the richness and diversity of learners’ empirical world, active construction, social interaction, and the situational nature of learning. That learners are builders of their own knowledge is an important theoretical basis for blended learning. It is convenient to use various mediated tools in blended learning. Thus teaching can be placed in a certain context, which can stimulate students’ learning interest and allow them to actively construct meaning (Hung 2001). Blended learning can not only promote in-depth, face-to-face communication of all parties through offline teaching, but also promote broader and longer in-depth discussions through the establishment of online virtual communities, in which participants can have multilateral collaboration and even cross-cultural communication to achieve corresponding learning outcomes (Lam 2015). Blended learning is more likely to provide a way for students to learn independently, pay attention to the construction of an autonomous learning environment, and then enhance the dominant status of students (Gharacheh et al. 2016). Due to the seamless connection between online and offline teaching, more activities can be carried out from class to out-of-class.

The guiding role of humanism in teaching and learning

Humanistic psychology was first proposed in the 1960s and prevailed in the 1970s. It is grounded in the belief that people are innately good and will grow and develop if provided with suitable conditions. Humanism advocates respect for human values and self-actualization and proposes that education should meet the actual needs for learners’ development of human nature. The typical representatives of humanism are Maslow and Rogers.

Abraham Harold Maslow (1908–1970) proposed the hierarchy of needs theory, based on which he further proposed the motivational theory of student learning and development.

The hierarchy of needs theory believes that people’s needs are diverse, and these needs can be divided into 7 levels arranged in a ladder according to their nature (Maslow 1970).

The hierarchy of needs has the following relationships: first, after the needs of the lower layer are satisfied, the needs of the higher layer will appear and dominate the individual’s behavior. Second, all needs can be divided into two categories: basic needs and growth needs. Basic needs include the first four levels of needs, all of which are directly related to human instincts, and the satisfaction of which is beneficial to one’s physical and mental health. The last three levels of needs are growth needs, which are driven by the development of one’s self-potential, and the satisfaction of which will bring the greatest degree of happiness to the individual.

Human needs determine their motivation, which means that the nature of needs affects the nature of motivation and the intensity of needs affects the intensity of motivation. Among all the needs, self-actualization is the central idea of Maslow’s motivation theory. Self-actualization means that all organisms are born with special potential, which is also an internal need of the organism. The desire to satisfy such a need drives the organism to realize its full potential.

Carl Ransom Rogers (1902–1987) pioneered “client-centered therapy”, believing that each individual has the potential for healthy growth. As long as a friendly, supportive, and sincere atmosphere is created for patients, the patient will recover on their own with no need for treatment.

During psychotherapy, Rogers developed the theory of personality, in which the notion of self or self-concept becomes the central focus. Self-concept believes that people are innately motivated by “self-enhancement”, which is manifested as the individual’s tendency to maximize their potential. This is the most basic motive and purpose of man and is the same as the Maslow motivation theory.

In addition, Rogers unequivocally proposed to cultivate a “whole person”. It is believed that traditional education only emphasizes cognition, but abandons any emotion associated with learning activities and denies the most important part of itself, which leads to the separation of knowledge and emotion in education. He believed that the ideal education is to cultivate a “whole person” who is “integrated in body, mind, feelings, spirit, and intellect” (Rogers, 1982). “Educated people only refer to those who have grasped how to learn and how to adapt to changes, and realized that no knowledge, only the process of seeking knowledge, is reliable.” To achieve this teaching objective, the autonomous learning of learners and the sincere attitudes that teachers show to learners are indispensable. Rogers believed that the key to teaching is not lesson plans, teaching skills, teaching resources, or teaching methods, but the relationship between teachers and students. To this end, teachers should fully trust students to develop their potential, respect learners’ feelings and personal experiences, treat learners with their “true” self, and have empathy. With leaners at the center of teaching, both schools and teachers should work for this learner-centered education (Rogers et al. 2012).

Rogers believed that learning is “meaningful” and “self-initiated” and he valued ​the relationship between learning materials and learners’ real life (such as learning interests, expectations, and needs). It is proposed that teachers should be facilitators and adopt a “nondirective” approach. Teachers and learners must gain mutual trust and follow eight principles: first, teachers and students jointly formulate curriculum plans and management methods and share responsibilities. Secondly, teachers provide students with various learning materials, including their own learning experience, books, reference materials, etc. Thirdly, learners’ exploration of their own interests should be taken as an important teaching resource and learners should be required to make a learning plan independently or with peers. Fourth, a good atmosphere for learning should be established. Fifth, the focus of learning is not on the content, but on the continuity of the learning process; the goal of teaching is not to have students master “what they need to know”, but to know how to master “what they need to know”. Sixth, learning objectives should be set by learners themselves and the realization of this goal should be promoted through the “self-training” of learners. Seventh, the learning results should be evaluated by students. Eighth, learners should be encouraged to display immersive emotions and reasoning in the learning process from the beginning to the end, so that learning can become an integral part of their lives and behaviors.

Both Maslow and Rogers pointed out that education, instead of being received from outside, should be self-initiated by students. Schools and teachers should create a good educational environment and a friendly, supportive, and sincere atmosphere for students. In this way they can have their basic needs satisfied and in turn spontaneously pursue self-actualization out of growth needs, fully tapping into their potential and achieving their value.

As a powerful supplement to behaviorism and cognitivism, the philosophical thoughts and learning theory of humanism have important guiding significance for teaching, especially in blended learning.

Connectivism and blended learning

Connectivism learning theory was proposed by George Simmons and Stephen Downes in 2005 (Siemens 2005; Downes 2005). The theory was born at a time when human society, with the challenges brought by rapid changes in and emergence of knowledge, tended to be digitalized, networked, and intelligent. It is an important theory to explain how learning occurs in the network age. This theory believes that knowledge is constantly changing and is a network phenomenon (Downes 2012); learning is not only a process in which connections are established and networks are formed, but also one that promotes the formation and connection of internal cognitive neural networks, conceptual networks, and social networks (Siemens 2005). In order to maintain the continuous flow and growth of knowledge, it is necessary to continuously establish, maintain and update connections in complex environments. This theory provides a new perspective for interpreting the learning mechanism in the Internet age and developing instructional designs in cyberspace more effectively.

Siemens proposed eight principles in his paper “Connectivism: A Learning Theory for the Digital Age” (Siemens 2005), which was further supplemented several years later, constituting of the 13 basic principles of connectivism.

  • Learning and knowledge rests in diversity of opinions.

  • Learning is a process of connecting specialized nodes or information sources.

  • Learning may reside in non-human appliances.

  • Learning is more critical than knowing.

  • Maintaining and nurturing connections is needed to facilitate continuous learning.

  • Perceiving connections between fields, ideas, and concepts is a core skill.

  • Currency (accurate, up-to-date knowledge) is the intent of learning activities.

  • Decision-making is itself a learning process.

  • The integration of cognition and emotions in meaning-making is important.

  • Learning has an end goal—namely the increased ability to “do something”.

  • Organizational and personal learning are integrated tasks.

  • Learning happens in many different ways. Courses are not the primary conduit for learning.

  • Learning is a knowledge creation process, not only knowledge consumption.

The connectivism learning theory provides new teaching ideas that adapt to complex network environments and new knowledge concepts, thus it can best reflect the normality of social learning in the current and future network environments (Duke et al. 2013). It is conducive to not only promoting innovations in complex and rapidly changing fields, but also training and developing learners’ learning ability and literacy in the digital age, providing them with a broader perspective to grasp the ever-changing growth of knowledge and to adapt to the development of society (Cabrero and Román 2018).

Connectivism learning involves both the consumption and production of content. The contribution of learners can expand in the network, such as reflection, critical comments, linked resources, the creation and communication of other digital knowledge, and problem solving (Anderson and Dron 2011). The continuous expansion, maintenance, and development of learning networks are the key to maintaining the timeliness and effectiveness of learning among individuals and groups. This point of view also affects the focus of the instructional design in blended learning under the guidance of connectivism, which has shifted to building an ecological environment that is conductive to network development and knowledge growth (Carreño 2014).

1.3.4 Curriculum Theory and Blended Learning

Curriculum is related and subject to educational goals and objectives, serving as the concrete embodiment of objectives and as the basis for achieving educational goals. In the meantime, it also constrains teaching and learning modes and strategies. As a theory and method system for curriculum design, the curriculum theory is established on different cognition and value orientations of the disciplines, individual psychological characteristics, and social needs. After the middle of the twentieth century, different curriculum theory genres emerged, such as the knowledge-centered theory, learner-centered theory, and social-centered curriculum theory, all of which are the theoretical basis for the curriculum design of blended learning.

Knowledge-Centered curriculum theory

The development of knowledge-centered curriculum theory involved Herbert Spencer’s substantive curriculum theory and Johann Friedrich Herbart’s intellectualism theory in the nineteenth century, plus the essentialism proposed by Johann Friedrich Herbart and Michael John Demiashkevich, Robert Maynard Hutchins’ perennialism, and Jerome Bruner Seymour Bruner’s subject curriculum theory in the twentieth century.

Intellectualism mainly refers to the genre represented by Johann Friedrich Herbart (Strozier 2002). It emphasizes knowledge and its associated intellectual and rational values and advocates knowledge transmission and intelligence development as the basis and purpose of education and teaching and learning processes. It is also emphasized that imparting knowledge is also education, edification, and training, and is the basic approach to provide moral, aesthetic, and religious education.

The main representative of substantive curriculum theory is Herbert Spencer. He defined the purpose and task of education as teaching individuals how to live. Since only science can prepare people for a full life, the knowledge of science is of most value, and thus curricula should be composed of practical scientific knowledge.

The main representatives of essentialist curriculum theory at the early stage include William Chandler Bagley, Michael John Demiashkevich, and F. Alden Shaw. This genre believes that the ultimate purpose of education is to promote social progress and improve the level of democracy. The key factors that determine whether society will advance and develop are personal morality and wisdom, which can be found in excellent cultural heritage from history. Therefore, course content should include common and unchanged cultural elements in cultural heritage, which are the fundamental core of social knowledge.

The main representatives of perennialism curriculum theory include Hutchins of the United States, Alain of France, and L Stone of the United Kingdom (Otiende and Sifuna 1994). This genre believes that the nature and purpose of education and curriculum content are eternal; traditional “eternal disciplines” that involve intellectual training are more valuable than practical disciplines. Those “eternal disciplines” with the most valuable knowledge are the most appropriate for schools to include.

Subject curriculum theory, developed in another wave of American education reform led by the noted American psychologist Jerome Seymour Bruner, focuses on satisfying the needs of developing the intellectual resources of modern human beings. The basic ideas of this reform are included in Bruner’s book, The Process of Education, which expounds the four key ideas of this curriculum reform. First, to learn any discipline is mainly to master its basic structure and to master the basic attitude or method of learning the discipline; second, the fundamentals of any discipline can be taught in some form to students of any age; third, teaching in the past only paid attention to the development of learners’ analytical thinking, but in the future, attention should be paid to the development of learners’ intuitive thinking; fourth, the best motivation for learning is to be interested in the learning resources themselves, instead of overemphasizing external stimuli such as rewards and competitions. Among these four key ideas, the core is the basic structure of disciplines.

Knowledge-centered curriculum theory is based on discipline knowledge to explain the curriculum. All knowledge-centered curriculum theories focus on which knowledge is most valuable.

Learner-Centered curriculum theory

The learner-centered curriculum theories originated in the twentieth century, and now mainly include the humanistic curriculum theory represented by Abraham H. Maslow and Carl Ransom Rogers, the empirical curriculum theory represented by John Dewey, and the existential curriculum theory represented by William Morris. With students as the focus, the learner-centered curriculum theories believe that curriculum content should change as students change during the teaching and learning process.

The founders of humanistic curriculum theory are Maslow and Rogers. The theory advocates considering people as a whole, rather than dismembering people’s psychology into several parts that cannot be integrated. It is believed that the fundamental value of education is to help people realize their potential and meet their needs. The purpose of education is to cultivate “a whole person” with good personalities, harmonious development, and freedom. Such a “whole person” can fulfil their potential. In other words, their needs at all levels are met. Also, the harmonious unity of emotional development and cognitive development is achieved. These should be unveiled throughout the entire process of curriculum development, implementation, and evaluation. Humanistic curriculum theory overemphasizes the importance of the “individual” and the values of individualism, which can be considered as its limitations.

Dewey is the representative of the empirical curriculum theory. In the past, curriculum theory witnessed a long-term battle between subject-centered and child-centered instruction. At the beginning of the twentieth century, Dewey resolved this conflict with his unique concept of experience and established the unique empirical curriculum based on naturalistic empiricism (Dewey 1963). Dewey (2001) shared four key ideas about the empirical curriculum theory in his book, Democracy and Education. First, education is continuous reconstruction or reorganization of experience, which adds to the meaning of experience, and which increases ability to direct the course of subsequent experience (p. 81–85). Second, “education as growth” (p. 46). Growth is a natural process, in which people’s habits, minds, and capacities continually grow and improve. Third, “Education as a Necessity of Life”(p. 5). Education itself is the process of life instead of preparation for future life.” Fourth, “Education as a Social Function” (p. 14). If school education is organized according to the form of social life, as a tool and a means to promote social progress and realize the democratic ideal, schools become a form of social organization and social life.

Existential curriculum theory is an educational trend based on existentialism. Existential educational philosophy emphasizes that the main purpose of education is to serve individuals. Education should guide people to become aware of their own environmental conditions, teach individuals to live spontaneously and authentically, and facilitate their smooth engagement in their meaningful existence. The whole emphasis of curriculum for schools must shift from the things to personality. It is advocated that the ideal curriculum should recognize individual differences in experience and take the interests of learners as the basis for learning plans and activities. It advocates activity-based learning starting from learners’ needs. It emphasizes that students have freedom in group and individual activities and recommends the use of a “dialogue” style for individualized learning. Also, it emphasizes reflection and enlightenment in the learning process, against subject-centered learning.

Social-Centered curriculum theory

Social-centered curriculum theory is also known as “social reconstructionist curriculum theory” and its main representatives are George Counts, Harold Rugg, Theodore Brameld, and Paulo Freire. This curriculum theory believes that the fundamental value of education is for social development, emphasizing social problems, and social transformation. It is believed that schools should focus on social transformation rather than personal development. The purpose of education is to “transform society”, according to the subjective blueprint. Schools are the main tools for forming a “new social order”. To this end, school curricula should be organized around the “central issue” of social transformation. The value of the curriculum is social value. The curriculum is the means for realizing the future ideal society. The four key ideas of this theory are as follows: first, the goal of the curriculum is to transform society. Second, the curriculum is centered on a wide range of social issues, which is decided by educators, according to the needs of the society. Third, the curriculum should be organized based on solving practical social problems, rather than subject knowledge. Fourth, in terms of learning strategies, students should be involved in social life as much as possible to enhance their adaptability to social life.

Curriculum theory and blended learning

Knowledge-centered curriculum theory, learner-centered curriculum theory, and society-centered curriculum theory all have different emphases, each of which is important to the current society. Therefore, the design, implementation, and evaluation of the curriculum of blended learning should integrate the above three theories. It is advocated that a curriculum of blended learning should be based on learners’ own needs, interests, development, and self-realization and pay attention to social problems and social needs. Through systematic learning and practice of disciplinary or interdisciplinary knowledge, such a curriculum should be able to meet the needs of social development.

From the perspective of the relationship between the system and the environment, blended learning takes social needs and problems as the input of the environment to the system so that the learning objectives and content can meet the social requirement to students. Blended learning has reshaped the existing form and organization of knowledge, broken down the exclusive nature of disciplinary knowledge in traditional teaching, and thus blurred the boundaries among disciplines. In blended learning, knowledge is identified and selected according to the learning objectives. The learning and application of knowledge are strengthened so that the ability of learners can be improved to meet the needs of social development. Blended learning provides content, resources, and learning paths that suit students’ characteristics to promote students’ self-realization, which represents the concept of learner-centered curriculum. In short, many curricular practices of blended learning are based on project-based learning or problem-based learning. The content of blended learning has focused more on solving specific problems, such as social problems. In the online environment, the learner-centered approach enables learners to set up personalized learning goals, have the autonomy to work on their learning progress, and select the curriculum according to their own needs. In this way, learners can enhance their capabilities of knowledge building and autonomous problem-solving skills.

1.3.5 Instructional Theory and Blended Learning

The design, implementation, and evaluation of curriculum and instruction of blended learning should follow the foundational principles of learning and teaching. In the following section, several major pedagogical theories for guiding blended learning will be introduced.

The theory of Mastery Learning and its implications for blended learning

The theory of mastery learning was founded by Benjamin Bloom and his colleagues. The so-called “mastery of learning” refers to supplementing classroom teaching and learning with frequent and timely “feedback-correction” sessions, in which students can have sufficient study time and receive individual help, so that they can master a unit and continue on a more advanced one, and thereby meet the standards set by the curriculum objectives. The theory of mastery learning contains two implications: first, it is an optimistic theory of teaching and learning; second, it is a set of effective individualized teaching and learning practices that can help most students learn. The core idea is to allow each student to have enough study time. As long as each student is provided enough study time that suits them, they should be able to achieve their learning objectives.

Bloom further pointed out that there are three variables that affect academic achievement: firstly, cognitive entry behaviors include learner’s aptitude and cognitive structure level. They account for 50% of learning. Secondly, affective entry characteristics refer to the integration of non-intellectual factors, such as the learner’s affection, attitude, interest, or confidence. They account for 25% of learning. Thirdly, the quality of instruction refers to whether the presentation, explanation, and arrangement of each element of learning tasks are suitable for learners. It accounts for 25% of learning.

Blended learning can facilitate the realization of mastery learning theory. First, for blended learning, it is more convenient to understand learners’ cognitive level in advance and use online learning resources to enable students to acquire knowledge required at an early stage. Moreover, designing blended learning activities in which students are interested and encouraging students through various ways can facilitate learners’ emotional engagement. Additionally, the online learning space can be fully utilized to provide personalized help and allow an individualized pace, thereby ensuring every learner to achieve their learning objectives.

First Principles of Instruction and their implications for blended learning

Professor M. David Merrill of Utah State University in the United States studied the common basic principles underlying instructional design theories and models. He summarized five principles (Merrill 2002). First, problem-centered: Learners learn more when they acquire concepts and principles in the context of real-world tasks. Second, activation: learners learn more when they activate relevant previous knowledge. Third, learners learn more when they observe a demonstration of the skills to be learned. Fourth, application: learners learn more when they apply their newly acquired knowledge and skills. Fifth, integration: learners learn more when they reflect, discuss and integrate their new skills in their everyday life.

Merrill believed that if the First Principles of Instruction can be applied, the effectiveness of teaching strategies will gradually improve. If the principle of “demonstration” is applied, effectiveness will reach the first level; if the principle of “application” is implemented, effectiveness will reach the second level; if the principle of “problem-centered” is implemented, the effectiveness level will reach the third level; if both of the principles of “activation” and “integration” are applied, the level of teaching effectiveness will be improved to a higher level.

The First Principles of Instruction can be used directly to guide the instructional design of blended learning and its implementation.

Scaffolding instruction

“Scaffolding”, originally referring to temporary platforms used to assist construction, is used as a metaphor for the conceptual framework that assists students in problem solving and meaning construction.

The theoretical basis of “scaffolding instruction” originated from the social constructivism founded by the noted psychologist Lev Vygotsky of the former Soviet Union. There are two related basic viewpoints. One, the sociocultural theory, holds that higher mental functions are social by their origin. Higher mental functions, including judgment, reasoning, imagination, intentional recall, will, higher emotion, and language, initially exist as an activity content or form among people. They are internalized by students, as students’ mental ability or inner mental process. Therefore, learning activities serve as important approaches for students to promote the development of their higher mental functions in the context of social interaction with teachers and peers. Second is the Zone of Proximal Development (ZPD) theory, which is “the distance between the current level of development and the level of their potential development” (Vygotsky 1980). The former refers to the ability to solve problems independently, while the latter refers the ability to solve problems under the guidance of an adult or in collaboration with more capable peers.

Instruction makes ZPD a reality and creates a new ZPD. The distance between the two levels is dynamic. Everyone’s ZPD is different. In terms of instruction, it is necessary for teachers to fully consider learners’ current level of development, set higher developmental requirements for students according to their proximal development zones, and provide personalized scaffolding.

The instructional design of blended learning can refer to the design of scaffolding instruction theory, namely to build a scaffolding according to the requirement of the zone of proximal development; to create a problem solving scenario to generate a cognitive gap; to guide students to independently explore knowledge construction with the help of the scaffolding built by the teacher; to strengthen knowledge construction through the communication between student–student and teacher-student; and to adopt multi-dimensional evaluation for diagnostic and reflective learning.

Activity Theory and its implications for blended learning

Activity Theory was proposed by Lev Vygotsky and enhanced by former Soviet Union psychologists Alexei Nikolaevich Leontyev and Alexander Romanovich Luria. It is the product of sociocultural activity and sociohistorical research. Activity theory emphasizes the bridging role of activities in the process of internalization of knowledge and skills. Activities are the basis of psychology, particularly for the occurrence and development of human consciousness, while human activities are objective and social.

In instructional design, the subjects are the students and the object is learning objectives, which are affected and changed by the subjects through certain activities. The community refers to other common learners except the students themselves, such as teachers, classmates, other personnel, etc. The tools can be understood as part of the instructional environment, including the design of hardware and software used in the instructional process. The rules are used to coordinate subject and community, as restrictions or agreement in teaching and learning activities. The division of labor means that different members must complete different tasks in the teaching and learning process.

According to activity theory, blended learning should fully utilize technology as a “tool” to help students to achieve their learning goals. At the same time, the rules that need to be followed should be fully designed in the learning activities involving community and individuals; if there are tasks, the division of labor should be well designed to ensure the effectiveness of blended learning.

Community of Inquiry

In 1999, the theoretical framework of the Community of Inquiry for the online learning environment was proposed by Randy Garrison, Terry Anderson, and Walter Archer of the University of Alberta in Canada (Garrison et al. 1999).

There are three core elements of teaching and learning in the Community of Inquiry theory proposed by Garrison et al.: cognitive presence (Garrison et al. 2001), social presence (Rourke et al. 1999) and teaching presence (Anderson et al. 2001). Garrison specified the categories and indicators of the three presences (Garrison and Arbaugh 2007).

The focus of the community of inquiry is the creation of educational experiences, which need to adhere to the following eight principles: first, establish purposeful and active inquiry activities. Second, plan for preparing critical thinking through critical reflection and discourse. Third, plan for building trust and creating an atmosphere that supports open communication. Fourth, establish a learning community and form cohesion. Fifth, establish mutual respect and responsibility. Sixth, plan the curriculum content, learning method, and learning time, and effectively monitor and manage critical dialogues and collaborative reflection activities. Seventh, sustain inquiry that moves to a resolution. Eighth, ensure assessment is congruent with intended processes and outcomes.

The following section elaborates on the three community of inquiry presences. Cognitive presence refers to the learners’ ability to construct and confirm meaning on their own through continuous reflection and discourse (Anderson et al. 2001). It includes four phases, namely triggering events, exploration, integration, and resolution (Garrison and Arbaugh 2007). Specifically, the process consists of a problem or task designed to trigger students for further inquiry; exploration for relevant information or knowledge, analysis, and integration of different perspectives and understandings; and solutions to the problems (Garrison et al. 2000).

Teaching presence refers to the design, facilitation, and guidance of cognitive and social process so that learners can achieve personally and educationally meaningful learning outcomes. According to Anderson et al. (2001), there are three categories in teaching presence, namely, instructional design and organization, discourse facilitation, and direct instruction. The main tasks of teaching presence are to create curriculum content; design learning activities and methods; set learning activity sequences; effectively use communication media; organize, accommodate, and manage purposeful critical dialogues and collaborative reflection activities; and provide students with timely feedback. Teaching presence encourages learners to become investigators with metacognitive awareness and metacognitive strategies in collaborative inquiry.

Social presence refers to the learners’ ability to project themselves socially and emotionally, thereby being perceived as “real people” in mediated communication (Short et al. 1976). Social presence consists of three components: affective expression, open communication, and group cohesion.

According to the theoretical model of the Community of Inquiry, the three elements are interrelated and reciprocally influence each other. Partially overlapping the three elements will generate meaningful educational experiences.

The revised CoI framework introduced three external factors apart from communication medium, namely educational context, discipline standards, and applications (Garrison, 2016).

Critical thinking is one of the ultimate goals of higher education. The CoI framework can play an important role in the development of students’ critical thinking skills in blended learning. Teachers need to understand and make full use of the three elements of CoI, facilitate in-depth and meaningful learning through collaborative learning activities and reflective dialogues involving critical thinking, and help to achieve student development goals.

1.4 Models of Blended Learning

The previous sections have first discussed the psychological and pedagogical basis for the emergence and development of blended learning, then elaborated on the theoretical foundations (system theory, educational communication theory, learning theory, and curriculum theory) for designing ideal blended learning. In this section, the theory of blended learning will be illustrated, including the blended learning model (namely the plan of blended learning based on theoretical foundations), the instructional design process model of blended learning (namely the process of designing blended learning), and the practice model of blended learning, which explains how to blend in practice. This section will first elaborate on the blended learning model.

A instructional model refers to a relatively stable interaction relationship among various instructional elements designed and gradually developed through practice and guided by educational philosophy that aims to achieve specific learning objectives. Such a model includes the integration of various elements of instructional process, instructional procedures, and corresponding strategies and evaluation methods.

Next, several commonly used instructional models and their applications in blended learning will be introduced. Designers can adopt a model according to their own instructional scenarios (such as learning objectives, learning content, and learners). It should be noted that the following instructional models can be applied in face-to-face, online learning, as well as online and offline learning.

1.4.1 Cognitive Apprenticeship Instruction

Before formal schooling, apprenticeship used to be the most common learning approach. In the ancient apprenticeship system, the apprentice observed the master’s work, communicated with the master, and tried to do the work. After having feedback from the master, the apprentice reflected and gradually developed skills that were as good as the master’s. This method enables learners to put into practice what they have learned because learning occurs in the real world. After the establishment of schools, and as learning has gradually been separated from real-life situations, it is difficult to develop learners’ higher-order cognitive abilities, such as applying knowledge to problem solving. To remedy the defects of traditional education, Collins et al. first proposed Cognitive Apprenticeship Instruction in 1989 (Collins et al. 1988). “Apprenticeship” indicates its inheritance or similarity with the traditional apprenticeship system, emphasizing that learning should take place in application scenarios, and knowledge and skills are acquired through the integration of observation of expert work and practice; “cognition” reflects a relatively strong practical significance, emphasizing that learning of generalized knowledge occurs in application scenarios to facilitate the application of knowledge in various scenarios. Cognitive apprenticeship aims to develop learners’ higher-order cognitive skills, such as problem-solving and reflective skills.

Six operational strategies for Cognitive Apprenticeship Instruction are recommended as follows: modeling, coaching, scaffolding, articulation, reflection, and exploration. Five socialization strategies are also recommended: situational learning, simulation, community of practice, intrinsic motivation, and cooperation.

Cognitive apprenticeship can be implemented in face-to-face learning. However, when the class size is relatively large, learning effectiveness will be compromised. Therefore, blended learning has more advantages in terms of providing scenarios, demonstrating through technical means, providing scaffolding, individual tutoring, and showing students’ practice.

1.4.2 Resources-Based Learning

Resources-based learning refers to an instructional model in which learners learn by interacting with a wide range of learning resources instead of attending classes. The learning resources refer to all available print and non-print media, including books and articles, audio-visual materials, electronic databases, and other computer-based, multimedia, and Internet-based resources. This instructional model aims to develop learners’ ability to learn or explore independently. At the same time, resources-based learning allows learners to choose the methods and pace they prefer to solve the same problem, with the flexibly to make adjustments according to their learning styles, interests, and competences. Therefore, the learning style with this instructional model is individualized or personalized. Resources-based learning usually involves the following steps:

  • Identify the problem. Key points of courses need to be changed to questions and learning objectives that students can explore.

  • Identify methods for collecting information. Students need instruction and guidance on information collection and the exploration of potential sources of information.

  • Collect information. During the process of information collection, students are required to be able to identify and select important information or facts relevant to research questions and to classify the information collected.

  • Use information. Students need to be instructed on how to use the information they have collected, and how to take note of sources of information.

  • Synthesize information for solving problems and present. Students are guided to organize information into a systematic, logical synthesis in order to solve the problem. Afterwards, students are required to present in oral, written, or other forms to demonstrate how they synthesized information to solve problems.

  • Evaluate. Students need to be provided the opportunity for evaluation and understanding on how to evaluate what they have completed. Evaluation and self-reflection are the highlights of resources-based learning (Awaludin 2019).

It can be argued that blended learning has advantages in implementing resources-based learning.

1.4.3 Project-Based Learning

Project-based learning (PBL) is a situational learning method based on constructivist theory (Lave and Wenger 1991). To be specific, when students actively build understanding by fully grasping concepts and applying them to real-world situations, they are able to acquire a deeper understanding of the learning materials. PBL is usually project-driven and requires students to integrate their understanding across disciplines. PBL projects must integrate fragmented discipline problems to address practical challenges and complex problems.

PBL is mainly composed of four core components, namely content, activity, context, and result. The implementation process is generally divided into six steps, namely learning relevant knowledge, selecting projects that comprehensively apply knowledge to create products (e.g., artifacts, schemes, etc.), forming groups, working in groups to complete projects guided by teachers, sharing project results, and conducting project evaluation. Steps can be added or deleted according to the implementation status of the projects. Blended learning can provide a better learning environment for the implementation of project-based learning.

1.4.4 Problem-Based Learning

Problem-based learning (PBL) emphasizes setting learning in complex and meaningful problem contexts. Students can collaboratively address real-world problems to acquire scientific knowledge, develop problem-solving skills, and become autonomous learners (Hmelo and Ferrari 1997). The steps of the PBL process are as follows (Chang et al. 2020):

  • Students are introduced to an ill-structured problem related to their real life.

  • Students collaboratively analyze the problem and discuss what they need to learn to solve the problem.

  • Students work on their own to find resources.

  • Students meet and discuss with group members regarding whether they can have a feasible solution based on the resources they found, which may need several rounds of attempts.

  • Students report the process of learning and problem solving in front of the whole class.

  • Students reflect and evaluate the whole process with their teacher and peers.

When it comes to blended learning, problem-based learning has the following benefits for students:

  • the construction of a more authentic problem context

  • timely communication and collaboration anytime, anywhere

  • autonomous learning based on resources

  • online Q&A areas for questioning and feedback

  • timely feedback for supporting their inquiry process.

1.4.5 Distributed Learning

Distributed learning, as an instructional model, allows teachers, students, and teaching content to be distributed in a decentralized way, so that teaching and learning can take place at different times and locations. The characteristics are:

  • distributed learning resources, which enable students to access good instructional resources everywhere

  • learner-centered, which means students can choose instruction resources suitable for themselves

  • collaboration and communication through interactive community, which enables students to acquire learning skills and social skills

  • knowledge construction through learning experience in the virtual environment (Li et al. 2007; Zhong and Zhang 2005)

Distributed learning can overcome the time and space limitations of traditional classrooms and expand the circle of teachers and peers. In other words, students can access instructional resources and resource persons on the Internet so that students can have cognitive views and experiences that are different from those locally to support their knowledge and meaning construction. Students can learn anytime, anywhere based on their needs. A blended learning environment is more conducive to the implementation of a distributed learning model.

1.4.6 Random Access Learning

Random access learning is an instructional model in which complex (or advanced) knowledge and skills are taught. Students can learn the same content several times for different purposes, through different channels, from different aspects, and with different methods, so as to gain a multi-faceted understanding (Spiro et al. 1995).

Due to the complexity and multi-faceted nature of problems in some fields, it is difficult to have a comprehensive understanding of the inherent nature of these complex problems and the interrelationships between things from one perspective or at one time. Therefore, random access learning advocates multiple attempts at the learning content for different purposes and from different perspectives. As a result, learners can have a qualitative leap in gaining a comprehensive understanding of the problem. In other words, learners will be able to improve their ability to understand complex interrelationships between things and flexibly apply the knowledge and skills acquired.

Random access learning, based on constructivist theory, helps to develop learners’ creativity and encourages their communication and cooperation. It is applicable in learning contexts including ill-structured and complex problem-solving scenarios, which focus on knowledge application and transfer.

Blended learning makes it more convenient to implement random access learning. Face-to-face learning is suitable for learners to share opinions about one issue from different angles, while online learning enables students to approach the same content from multiple angles by providing learning resources that involve different viewpoints of the same content. At the same time, students can take advantage of the discussion area on the platform to present and share their own opinions with others, which can promote the effective implementation of random access learning.

1.4.7 Flipped Classroom

The educational philosophy behind the flipped classroom is active learning, the core of which is to reverse the activities that take place inside and outside the classroom. That is, “the events that have traditionally taken place inside the classroom now take place outside the classroom and vice versa” (Lage and Treglia 2000).

Alten et al. (2019) summarized five advantages of flipped classrooms by reviewing the existing literature:

  • It requires students to have strong self-regulation learning ability and in turn helps to develop students’ self-regulation ability.

  • Students take the initiative to complete assignments in class with the help of teachers, avoiding cognitive overload when completing homework alone.

  • Students have more time for learning activities, which is an active, constructive, and interactive mode of participation.

  • Students have more opportunities to receive effective feedback and differentiated instruction from their teachers.

  • Finally, FTC is often assumed to be a promising pedagogical approach that increases student satisfaction about the learning environment.

Criticisms of flipped classroom include:

  • Video production is too time- and energy-consuming for teachers and places an excessive demand on learners’ abilities.

  • It takes up too much time after class and causes too much pressure on students.

The design framework of flipped classrooms should consist of 9 principles (Kim et al. 2014), specifically:

  • provide an opportunity for students to gain first exposure prior to class

  • provide an incentive for students to prepare for class

  • provide a mechanism to assess student understanding

  • provide clear connections between in-class and out-of-class activities

  • provide clearly defined and well-structured guidance

  • provide enough time for students to complete assignments

  • provide facilitation for building a learning community

  • provide prompt/adaptive feedback on individual or group works

  • provide technologies that are familiar and easy to access.

Teachers can refer to this framework to design flipped courses. The flipped classroom is a typical model of blended learning, which aims to establish an organic systematic integration between online and face-to-face learning activities.

1.5 Blended Learning Models and Blended Learning Practice Models

To realize the above-mentioned instructional models of blended learning and their learning objectives, the implementation process needs to be designed. From this design process is formed the design process model of blended learning (simply named the blended learning design model). The blended learning design model follows the common characteristics of general instructional design models and has its own uniqueness. This section first discusses the general learning design model to be followed during blended learning, then examines the special characteristics of blended learning design, discusses the blended learning design models that are based on these specific characteristic, and introduces some practice models of blended learning i.e., how to blend in practice.

1.5.1 Blended Learning Design Model

According to the levels of the system, the instructional design can be divided into three levels: “system centered” (such as professional program plans, curriculum, etc.), “product centered” (such as instructional software and resources, etc.) and “classroom centered” (from a unit that takes several hours of classroom teaching). The instructional design at the three levels share common elements of design, but the emphasis at different levels varies.

By summarizing thousands of models of instructional design, Wu (1994) formed the general model of classic instructional design. This model is designed based on learning theories, instructional theories, communication theories, and systems theories, including all elements of the instructional design process in a relatively systematic and holistic manner.

The general learning design model should be followed for blended learning design. In terms of different levels, blended learning has the design of a blended learning platform and blended courses for system-focused level, as well as a blended instruction process (several hours of classroom teaching) that is at a classroom-focused level. The development of a variety of instructional resources is required in blended learning, at the product-focused level. All elements of the general learning design model are also involved in blended instructional design.

At the same time, the particularity of blended learning also needs to be considered, compared with pure offline or online instruction, which should be the most important difference between the blended instructional design model and the general model of instructional design.

Compared with traditional face-to-face learning, blended learning extends and widens the teaching and learning time and space. Students can learn independently or cooperatively at anytime and anywhere at their own pace. At the same time, instructors are more likely to obtain a variety of relevant information about student learning and provide a personalized learning environment that is more appropriate for them by tracking their online learning traces with the support of big data and learning analytics. Compared with online learning, blended learning would dissolve the sense of alienation between teachers and students and the sense of isolation of students, offer a more flexible organization of teacher-student meetings, allow for group teaching of content suitable for face-to-face instruction, and thus increase the effectiveness of teaching and learning.

Stein/Graham’s design model of blended learning

Jared Stein and Charles R. Graham co-authored a book on blended learning, Essentials for blended learning: a standards-based guide, in 2014. They proposed the blended course design model when conducting research on blended learning in colleges and universities. Blended course design is a cyclic process consisting of three activities: designing, engaging, and evaluating. Stein and Graham emphasized that blended classrooms need iterative development and pointed out that the design of individual learning activities, courses, or units can be supported through continuous improvement of the three activities.

The design part of the model includes four components: designing learning goals and objectives, designing evaluation and feedback, describing learning activities that can achieve teaching goals, and adding online elements to the learning process. The process starts with learning outcomes, then designs corresponding assessment tasks, and finally creates activities for achieving learning outcomes. Teachers are encouraged to design a small part (such as a single course or unit) at a time, and further optimize the design after students have participated in blended learning activities and evaluated online and offline learning effectiveness. In order to support the implementation of instructional design, Stein and Graham (2014) provided a blended course design template in the book Essentials for blended learning: a standards-based guide.

Eagleton’s design model of blended learning

Eagleton (2017) proposed a blended learning intervention design model for the teaching of psychology in higher education, including three parts: identifying learning task needs (through pre-tests, learning outcomes, and student profile analysis), designing learning interventions (including developing and disseminating instructional strategies, learning strategies, and evaluation strategy) and evaluation.

  • Determining learning task requirements is divided into three sub-tasks: obtaining students’ personal profiles, pre-testing students, and specifying learning outcomes, i.e., learning objectives

  • Finalizing learning task needs based on basic student learning information and learning objectives, followed by learning intervention design (teachers’ teaching strategies, students’ learning strategies, forms of instructional content development and dissemination, and design of instructional evaluation); and

  • Evaluation (mainly feedback and slight adjustment of instructional programs in the implementation process).

In addition, Eagleton et al. argued that creating a blended learning program is a process that needs to take into account the ability of teachers, the infrastructure of the institution, and the learners’ acceptance of the new learning mode. The blended learning design can be integrated into the whole-brain learning model (Eagleton and Muller 2011). It is necessary to consider the differences in students’ information processing of the left brain and the right brain when learning different materials, and integrate the whole-brain learning model to design the learning content and learning form.

1.5.2 Blended Learning Practice Models

In blended learning, one problem to be faced is when to implement online learning and when to implement offline learning. Through blended learning and teaching practices, scholars have summarized some blended learning practice models. These models can help teachers to increase their knowledge and experiences of how to blend online and offline learning.

Zhu Zhiting’s three models of blended learning practice

Zhu and Hu (2021) summarized three models of blended learning practice, namely O2O, OAO, and OMO, and pointed out that blended learning would inevitably move towards OMO in the future.

O2O (Online to Offline) model refers to a learning environment based on online, offline, or online-to-offline practice. The teaching process mainly takes place offline, while an online learning environment serves as the triage. In a flipped classroom, the ‘students’ online learning determines offline teaching’ model is an embodiment of this type of triage. Another example is maker learning, in which tasks are provided online and explored offline. Learning in this model is mainly a one-way flow from online to offline. There are clear boundaries between online and offline.

OAO (Online and Offline) model refers to the integrated ‘dual store’ form that integrates online and offline practice organically. It is a model based on the integration of online and offline practice, with two-way online and offline intercommunication, interconnection, and mutual appreciation. There are clear boundaries between online and offline.

OMO (Online Merge Offline) model refers to a student-centered learning environment based on the comprehensive integration of online and offline practice, synchronously and asynchronously. Technical methods are used to bridge various structures, levels, and types of data online and offline; establish an ecology of online and offline merging through virtual and real learning scenarios; and realize a new teaching style of personalized teaching and service. This kind of environment is developing in the direction toward the ‘physicalizing of online space and virtualization of offline space’. There are two important changes in the development direction of the learning environment constructed by OMO: 1. the interface boundaries between online and offline is weakening and disappearing; 2. the learner has changed from “marching with heavy burdens” to “walking with ease”.

Michael Horn’s six blended learning models

Micaeal Horn of the Innosight Institute in the United States has identified six blended learning models (Horn and Staker 2011).

Face to face driven model is a blended learning model mainly based on face-to-face learning. Teachers deliver course content through traditional classroom teaching, supplemented by online course resources or review materials, so that students can learn independently at home, in the classroom, or the laboratory. Another approach to this model is for teachers to allow students to learn online course content at their own pace in the classroom. The role of the teacher in the process is to provide individualized instruction.

Online driven model is mainly based on online learning. Students primarily study online at a distance, with the option to attend face-to-face instruction. This model provides all learning content through dynamic management of online courses and uses remote synchronous interactive systems (such as video conferencing systems) or asynchronous interactive systems (such as BBS discussion areas) to conduct Q&A discussions with individual students and groups. This model can provide students with learning opportunities at any time and any place and provides more choices for students’ extracurricular activities.

Face-to-face and online rotation model: alternating between face-to-face and online instruction, students alternate between a period of face-to-face instruction and a period of online learning outside of the classroom. A flipped classroom is a form of this model, where students learn online course content in advance, at home and then come to the classroom to receive face-to-face instruction from teachers.

In the flex model, learning content happens online or face-to-face in groups/individual tutorials. Most students learn in an online environment. They can receive face-to-face instruction in the classroom, but the face-to-face instruction is only for group or individual tutoring. Students decide how to arrange the learning content and construct their knowledge at their own pace. While students can access course resources through mobile devices at home and in school or anywhere, teachers play a key role in facilitating learning with individuals and groups of students in a brick-and-mortar school. This model requires obtaining information through the Internet, no matter where the students are located.

Online lab model refers to learning in the computer lab and completing the interactions online. All course materials and teaching activities are completed in the computer lab. Students are supposed to learn independently by watching multimedia learning materials and interacting synchronously or asynchronously with teachers or classmates through video conferencing systems, forums, and e-mails. Although this model sets up a complete online course for students to learn at their own pace, the learning process is in the space of a brick-and-mortar school. Most course units are completed by students on their own, while some units require the collaboration of study groups of three to four students.

The self-blended model allows students to choose between online and offline learning. This is a personalized instructional model. Students can choose learning content online and learn based on their learning needs. Most of the learning is completed online, but students can participate in face-to-face classroom instruction. In the implementation of this model, to support students on the acquisition of relevant knowledge and learning tools, teachers need to prepare corresponding online courses in advance as necessary resources for students to complete learning tasks.