2.1 Introduction

This chapter focuses on a review of the literature on the theories, frameworks, and approaches that inform teacher professional development in vocational education. We first define the scope of vocational education and teacher professional competencies in this introduction. This is followed by an exposition of theories, frameworks, and approaches on teacher professional competency development that contribute to teacher professional development in vocational education.

2.1.1 Defining the Scope of Vocational Education

There has been a proliferation of terms used to refer to vocational education. According to Ouyang (2003), there are over 30 terms describing vocational education. They include Apprenticeship Training, Vocational Education, Technical Vocational Education (TVE), Occupational Education (OE), Vocational Education and Training (VET), Career and Technical Education (CTE), Workforce Education (WE), Workplace Education (WE), among others. Since 1999, the term of Technological and Vocational Education and Training (TVET) has replaced most of the other terms to because the “official” vernacular used in academic publications and official documents, particularly in UNESCO documents and policy statements. TVET was first adopted at the Second International Conference on Vocational Education held in Seoul, capital of South Korea in April 1999. This is the term used in this Handbook.

How should we define TVET? UNESCO-UNEVOC defines TVET as “comprising education, training and skills development relating to a wide range of occupational fields, production, services and livelihoods,” “as part of lifelong learning,” and that it “can take place at secondary, post-secondary and tertiary levels and includes work-based learning and continuing training and professional development which may lead to qualifications”. UNESCO-UNEVOC further points out that TVET helps learners to develop a wide range of skills such as learning to learn, “literacy and numeracy skills, transversal skills and citizenship skills” (https://unevoc.unesco.org/home/TVETipedia+Glossary/filt). This handbook adopts the above definition of TVET as our basic understanding when discussing issues in TVET.

TVET has been regarded as an important venue for achieving social equity, inclusion and sustainable development by UNESCO (https://unevoc.unesco.org/home/fwd2UNESCO-UNEVOC+-+Who+We+Are). In 2019, China released “The Implementation Plan for National Vocational Education Reform,” which promoted the importance of TVET by stating that “vocational education and general education are two different types of education with equal importance”.

2.1.2 Defining the Basic Tenets in TVET Teachers’ Professional Competencies

TVET teachers’ professional development has never been so crucial as it is today when rapid changes in education and industry are transforming TVET in every possible way. TVET teachers must develop and upgrade their professional knowledge, teaching competencies, and innovative teaching strategies to meet the diverse and personalized educational requirements of industry and learners (Guthrie, 2010). This is a lifelong journey that requires the concerted efforts from both teachers as individuals and from governments and institutions. UNESCO and other relevant international organizations such as UNEVOC have played a major role in TVET teachers’ development throughout the world. As promoted in “the UNESCO TVET Strategy 2016–2021,” competent TVET teachers are essential for the quality and development of TVET, because they are the key agent for equipping future workforce with knowledge, skills, and disposition to meet the needs of a rapidly changing labor market, and contribute to the sustainable development of the society.

What professional competencies are required of today’s TVET teachers? Before we discuss teacher competencies, we need to define what competency entails in this study to lay a foundation for building our understanding of teacher competencies. The definition we adopted here reflects the established arguments in the literature. That is, a competency refers to the combination of one’s knowledge, skills, and personal attributes such as attitudes, disposition, beliefs, and values that makes one professionally competent (Koster & Dengerink, 2008; Rychen & Salganik, 2003). In this handbook, we also use the word ‘competence’ in a broader and more general sense to refer to one’s ability in accomplishing something.

In this handbook, we make a clear distinction between teaching competencies and professional competencies in that the former focuses on pedagogical capacities of a teacher such as knowledge and pedagogical skills while the latter involves other attributes as a teacher such as attitudes, beliefs, and dispositions, in addition to teaching competencies. In other words, teacher professional competencies are more inclusive than teaching competencies. We also stress that the requirements for teacher professional competencies have never ceased to evolve and expand over time. This capacities approach to the understanding of teachers’ competence is largely in line with the dominant views in scholarly debates about basic capacity requirements for teachers (Feiman-Nemser, 2001; Grant, 2008; Williamson McDiarmid & Clevenger-Bright, 2008). There is a substantial body of literature on teacher capacities and competencies in general education (see a review by Caena, 2011). In her comprehensive review of the literature on approaches and debates regarding the definitions of teacher competence, Caena (2011) synthesized the key elements of teacher competence requirements as follows. In terms of the requirements of knowledge, the following areas were identified:

  • subject matter knowledge

  • pedagogical subject knowledge

  • pedagogical knowledge

  • curricular knowledge

  • educational sciences foundations (intercultural, historical, philosophical, psychological, sociological knowledge)

  • contextual, institutional, organizational aspects of educational policies

  • issues of inclusion and diversity

  • new technologies

  • developmental psychology

  • group processes and dynamics, learning theories, motivational issues

  • evaluation and assessment processes and methods (p. 28).

—In terms of skills, a teacher should possess:

  • planning, managing, and coordinating teaching

  • using teaching materials and technologies

  • managing students and groups

  • monitoring and assessing learning

  • collaborating with colleagues, parents and social services

  • negotiating skills

  • collaborative, reflective, and interpersonal skills for learning in professional communities

  • ability to adapt to multi-level dynamics with cross-influences (from government policies to student, classroom and school dynamics)

  • ability to draw conclusions and decisions on the basis of interpretations of evidence and data, for teaching and learning enhancement (p. 28).

—In terms of values, the following were identified:

  • epistemological awareness (i.e., about relevant issues of the features and historical development of the subject area and its status, as related to other subject areas)

  • dispositions to change

  • commitment to promoting the learning of all students

  • dispositions to promote students’ democratic attitudes and practices, as future European citizens

  • dispositions to flexibility and ongoing learning

  • dispositions to examining, discussing, questioning one’s own practices (p. 28).

We recognize that teacher competencies are complex, multifaceted, and evolving with time, and that the above lists are not exhaustive. However, they can be used as a checklist when discussing teachers’ competency standards and requirements. Although these elements were gleaned from the literature relating to general education, they are readily applicable to TVET. We also noted that transformative changes in education and our society have occurred in the last decade since Caena’s (2011) review was conducted and that teacher competencies should be revisited and updated accordingly. This is especially true with teachers’ ICT competencies as we enter the digital era. In TVET, developing teachers’ ICT competence is not an option, but a must due to the digital transformation happening on campus and in industry. For both teachers and learners, existing knowledge and skills need to be upgraded and new skills need to be developed to meet the changing demands from workplace and personal growth. In view of such needs, many scholars and practitioners in TVET have proposed new competencies required of TVET teachers today. For example, Han et al. (2019) suggested that core ICT competencies for TVET teachers can consist of seven dimensions: awareness, attitude, knowledge, skills, learning design and development, implementation, and evaluation. To Zhang and Rong (2011), TVET teachers should be competent in the following six aspects as far as ICT supported learning is concerned: understanding ICT supported/enabled learning, curriculum and assessment development, pedagogical proficiency, proficient use of ICT and technological equipment, ability to create ICT-supported learning environments, and ability to self-develop with the support of ICT. A more detailed discussion on TVET teachers’ digital teaching competencies is contained in the next chapter.

2.2 Frameworks and Approaches Adopted in TVET Teachers’ Professional Competency Development

This section briefly reviews some key frameworks and approaches that have been adopted in TVET teachers’ professional development. Empirical studies implementing and evaluating these frameworks and approaches are also reviewed for a better understanding of these frameworks and approaches.

2.2.1 The TPACK Framework

As a framework that describes the professional knowledge needed for teaching with technology, TPACK (Technological pedagogical content knowledge) was introduced by Koehler and Mishra (2005). The three core components of knowledge in the TPACK framework are content knowledge (CK), pedagogical knowledge (PK), and technological knowledge (TK). The other components of pedagogical and content knowledge (PCK), technological content knowledge (TCK), and technological pedagogical knowledge (TPK) in TPACK are knowledge developed through the interactions between and among these bodies of core knowledge mediated by the use of technology (Koehler & Mishra, 2009). In the words of Cox and Graham (2009), TPACK is “teacher’s knowledge of how to coordinate subject-or topic-specific activities with topic-specific representations using emerging technologies to facilitate student learning” (p. 64).

There is a large number of studies that have employed TPACK to investigate vocational education teachers’ competencies and documented empirical evidence for an in-depth understanding of vocational education teachers’ competencies. For example, Miao et al. (2016) surveyed 140 teachers from 13 vocational colleges in Chongqing, China, in regard to teachers’ perceived TPACK competencies. Their findings revealed that there was a tendency of overfocusing on the development of technological knowledge at the expense of the development of pedagogical and content knowledge. Therefore, they proposed that the professional development for TVET teachers should attach greater importance to pedagogical and content knowledge when integrating technological knowledge into teaching. Guided by the TPACK framework, Ran and Cai (2017) investigated the level of TPACK competencies of teachers who were both teachers and trainers in secondary vocational colleges in China. In view of the many challenges facing these teachers, they recommended to establish an in-company teacher training system, build learning communities, develop ICT competencies for instructional design and delivery, and implement professional development programs at different levels.

In recent years, the TPACK framework has undergone some updating and restructuring to reflect the changes and new demands in education, particularly those brought about by digital transformation. Adopting an andragogical approach, Arifin et al., (2020) revised the TPACK framework and proposed a new acronym “TAWOCK” to denote a Technology Andragogy Work Content Knowledge Model. This model was developed specifically for TVET. It is characterized by a learner-centered approach and takes workplace learning and training into consideration. Our literature review indicates that it is still a conceptual model at this stage in need of empirical validation. Another adaption of the TPACK framework to the TVET context was proposed by Tang and Bai (2021). With a strong emphasis on TVET related content, knowledge, and technological-pedagogical proficiency, this model aims to further our understanding of TVET teachers’ competency requirements in the 5G era. There are four parts in this adapted framework: V-TK (vocational technological knowledge), V-TCK (vocational technological and content knowledge), V-TPK (vocational technological and pedagogical knowledge), and V-TPACK.

2.2.2 The COMET Model

COMET stands for “Competence Development and Assessment in TVET.” This is a competence diagnostics model that was specifically developed for TVET. It takes into consideration the special features, or the diverse and complex requirements and demands of TVET, in terms of competence development and assessment in both the classroom and workplace. Originated in Germany in 2006 and led by Professor Felix Rauner, the COMET project has now been developed into an international research consortium participated by countries such as China and South Africa (Rauner et al., 2013a, 2013b). As commented by Lahn and Nore (2019) (Zhao & Rauner, 2020), the primary goal of this project was to establish a theoretical and methodological system to support the pedagogical work of TVET teachers. A secondary aim was to construct a benchmark for international comparisons that will inform policymaking and education reform in TVET. Rauner (2021) mentioned, “In less than a decade, the methods of competence diagnostics in accordance with the COMET test procedure have become an internationally established instrument for quality assurance and quality development in vocational education and training” (p. v).

Briefly, the COMET model, in some ways, can be regarded as the TVET equivalent of PISA (The Program for International Student Assessment). It offers a large-scale competence diagnostics method for quantitative evaluations of the advancement of students’ occupational competencies, career commitments, and professional identity. There are three interconnected dimensions in this model: the requirement dimension (competence levels including shaping competence, processual, functional, and nominal competence), the content dimension, referring to areas of learning at different levels (beginning, advanced, professional and expert), and the action dimension progressing from informing, planning, deciding, conducting, controlling to assessing). For a diagram of this model, see Rauner et al., (2013b), p. 42. Each dimension has its own theoretical and normative bases. Competence measurement instruments and test tasks based on COMET were also developed and evaluated by TVET researchers and practitioners around the world. Rauner (2021) provided a method manual book providing a detailed and updated discussion of this model and the relevant instruments for competence measurement developed since the inception of this model. One can also find empirical studies adopting this model and these test instruments in this book.

The COMET model was also adapted to teacher professional development in TVET to develop a TPD (Teachers of Professional Disciplines) competence and measurement model for TVET teachers. Its validity was confirmed by empirical studies such as the one reported in Zhao and Zhuang (2012). Their study largely confirmed the validity of the test tasks and the competence model.

2.2.3 The SMART Framework for Teacher Professional Development

In the last 10 years, terminologies such as smart learning, smart education, and smart learning environment have been frequently used by researchers exploring the affordances of ICT in supporting or enabling learning. While the lack of consensus on the definition of smart education is recognized in the literature (Hoel & Mason, 2018; Zhu et al., 2016), there have been many attempts to explore its theoretical basis, characteristics, and practical implications. The following defining features of smart education can be gleaned from the literature. Smart education involves, but is not limited to:

  • the creation of intelligent environments by using smart technologies and the adoption of smart pedagogies that facilitate personalized learning and empower learners to develop wisdom (Zhu & Bin, 2012).

  • a smart learning environment that is “effective, efficient and engaging” (Spector, 2014, p. 2).

  • a better and faster learning enriched by digital, context-aware and adaptive devices (Koper, 2014, p. 1).

The smart education concept has also been adopted in teacher professional development to meet the needs of teachers in a time of digital transformation. For example, Zhong (2020a, 2020b) investigated teacher development from the perspective of SMART education and proposed a SMART education framework to guide the professional development of teachers. The central tenet of this framework regards today’s teachers as smart teachers empowered by technology. This framework is composed of five interrelated constructs represented by S, M, A, R and T. S represents SMART-education directed; M refers to Self-managed; A is Adaptive; R stands for Reflective; and T means Technology-empowered.

2.2.3.1 SMART Education Idea Directed

Applying the concept of smart education to teachers’ professional development, this framework places a strong emphasis on advancing teachers capacities in fostering students’ abilities and skills in critical thinking, innovation, collaboration, communication, and problem solving. SMART education also requires teachers to develop digital competence to innovate teaching and improve student learning. Finally, SMART education also means the adoption of innovative evaluation models, and making evaluation more automated, intelligent, and personalized (Gu et al., 2021).

2.2.3.2 Self-Managed

Self-management is a crucial strategy for teachers’ lifelong development. The lifelong and continuing professional development of a teacher is essentially a process and result of self-management (Zhong, 2008). Self-management refers to the effective control and adjustment of self-awareness, emotion, and behavior on the basis of fully understanding how to achieve the goal. It is the active and effective monitoring and adjustment from self-awareness to behavior. The core of self-management is self-regulation, or the ability to actively participate in and be responsible for one’s own activities, including strategies, self-efficacy, self-efforts, and self-reflection. Self-management can be categorized into the following 10 focal areas: basic knowledge, self-awareness, goal management, resource management, time management, pressure management, emotion management, effort management, interpersonal relation management, and self-evaluation management (Zhong, 2015).

2.2.3.3 Adaptive

In the digital age, being adaptive should be a learning mode by default. As far as teachers’ professional growth is concerned, being adaptive means to have the ability to change in order to meet the demands of digital transformation. Thus, a SMART teacher needs to develop adaptability in the following four aspects:

  • Being self-driven: Teachers should be the active agent driving their self-development and lifelong learning. They should develop a sense of ownership of their learning and manage their professional development with a degree of independence and sovereignty.

  • Being smart in ICT-supported professional development: Teachers should develop the ability to use ICT and digital resources smartly to suit their own individual needs and support their professional development.

  • Personalizing learning in professional development: In the digital age, teachers’ professional development should identify individual differences and cater for individual growth through more targeted and customized learning design, teamwork, and role play. With the support of adaptive technology such an approach can maximize the potential of individual teachers.

  • DIY learning: DIY learning refers to self-organized learning often occurring at workplace. It is self-initiated, often an informal, lifelong learning empowered by technology and sustained by one’s adaptivity. DIY learning allows teachers to design and develop their own professional trajectory.

2.2.3.4 Reflective

This construct refers to teachers’ growth through reflection. Reflection is widely regarded as a determining factor in teachers’ professional development. Without reflection, there would be no continuous professional growth of teachers (Calderhead & Gates, 2003). Teachers’ reflection is the process in which teachers constantly improve their educational and teaching efficiency and student learning outcomes by reflecting on their teaching experiences and analyzing and correcting their own behaviors in teaching practice. The process features reflection on the practicality, pertinence, time-efficiency, self-examination, and procedure of their teaching process (Zhang, 2001). Metacognition and meta-learning are the core competencies of teachers’ reflective growth. Meta-cognition is a process of reflection, which involves reflection on one’s own current situation, future goals, potential behaviors and strategies, and expected outcomes. Meta-learning is closely related to metacognition. What is more important to teacher development is meta-learning that cultivates a growth mindset and a firm belief in change and development. It recognizes the importance of the intrinsic motivation of teachers in their continuous growth and development (Fadel et al., 2015). Teachers’ metacognition and meta-learning are premised on reflection, which in turn promotes teachers’ professional growth.

2.2.3.5 Technology-Empowered

Technology has empowered every aspect of education, creating a new ecology in education. SMART teachers must also be empowered by technology. Technological empowerment embraces both the enabling and augmenting power of technology. The former makes what is impossible possible and the latter makes what is powerful more powerful (Zhu & Peng, 2021). In this process, it is important to be rational. For instance, allowing machines do what is suitable for machines, people do what is suitable for people, and people and machines do what is suitable for human–machine cooperation (Zhu & Wei, 2018). Technologies and teachers will become a community to undertake educational tasks (Zhong, 2020a, 2020b).

2.2.4 Micro-credentialing

Micro-credentialing is a direct response to the demands for recognizing one’s constant efforts in upgrading knowledge and skills needed by today’s digitalized society. Together with other credentials such as digital badges and industry-recognized certificates, micro-credentials form part of the so-called alternative credentials that are gaining interest among learners from all walks of life in the last decades (Kato et al., 2020; OECD, 2021). European Commission (2020) defined micro-credentials as a “proof of the learning outcomes that a learner has acquired following a short learning experience.” and the acquired learning outcomes have been “assessed against transparent standards” (p. 10). According to Berry and Cator (2016), micro-credentials were competency-based, personalized, on-demand and shareable. They are also research-backed (https://digitalpromise.org/initiative/educator-micro-credentials/). OECD (2021) summarized 12 desirable characteristics of micro-credentials:

targeted (breath), rapid (duration), flexible (sequencing or timing), stackable (with institution), learning outcomes assessed (using sectoral or national assessment framework), external assurance of program or provider, portable (applicable to study programs in other higher education institutions), study load expressed in credits, located with National Qualification Framework, employer role in credential design/approval, wage or occupation reporting and self-sovereign digital identity (recipient ownership, vendor independence). (p. 4)

Micro-credentialing, empowered by online learning resources, Open Educational Resources (OERs) and emerging technologies such as online platforms and social media, offers a flexible way to personalize one’s micro unit learning and lifelong learning. It offers a new pathway for learners to receive formal recognition for learning of this kind, supplementing what formal educational programs lacks, in terms of flexibility. Micro-credential programs have been offered in schools, higher education (at both undergraduate and postgraduate levels), vocational education, and industry throughout the world. Their effectiveness has generally been recognized and confirmed (for a more detailed discussion on micro-credentials see OECD, 2021). In TVET, the importance of micro-credentials is highlighted for meeting the needs of the post pandemic workplace. As such, micro-credentials have been suggested to be extended to micro-apprenticeships (Seet & Jones, 2021).

Micro-credentials have also been adopted in teacher professional development in recent years. In view of the inefficiency of seat-time and workshop approach to formal teacher professional development programs and in recognition of teachers’ informal self-development efforts, many educational institutions around the world offer micro-credentials to their staff as a certification of skill development (OECD, 2021). For example, Digital Promise, a US non-profit organization, launched the first micro-credentials for K12 educators in the US in 2014. To date, it has partnered with over 50 organizations in the US to develop an ecosystem promoting micro-credentials to higher education institutions, schools, and other organizations (https://digitalpromise.org/initiative/educator-micro-credentials/). Micro-credentials meet the needs of the competency-oriented nature of teacher education reform in the US and reflect its outcome-driven approach in teachers’ professional development (Wei & Zhu, 2017). Crow (2017) promoted micro credentials as “an emerging learning design that shows promise for offering educators an on-ramp for identifying and meeting classroom-specific professional learning needs” (p. 4).

2.3 Theories Informing TVET Teachers’ Professional Development

This section reviews key theories that inform TVET teachers’ professional development. When reviewing each theory, we first explain the basic tenets of the theory and the scholarly debates surrounding the theory under discussion. Empirical studies are then cited to demonstrate how it has been applied to practice, with a particular focus on examples of its application in recent TVET teachers’ professional development, whenever possible.

2.3.1 Lifelong Learning Theory

The concept of lifelong, originating in the 1970s, had been confined to adult education until 1996 when the Delors Report (UNESCO, 1996) was published. In this report, OECD Education Ministers called for “lifelong learning for all” and adopted it as a framework to guide educational policy making (OECD, 2001). Up to this day, the framework has not only provided a broad basis for us to understand what lifelong learning entails, but also informed research and policy formulation in relation to lifelong learning. Rapid societal and technological changes in the twenty-first century have made lifelong learning part of the education system today. In particular, the launch of Sustainable Development Goal 4 (SDG 4) in 2015 by the United Nations has brought renewed global attention to lifelong learning. SDG 4 calls on Member States to “ensure inclusive and equitable quality education and promote lifelong learning opportunities for all” (https://www.un.org/en/academic-impact/page/sustainable-development-goals). In reviewing research on lifelong learning, the following perspectives have emerged strongly:

  • In terms of learning span, lifelong learning covers the whole course of one’s life, from cradle to grave (Commission of the European Communities, 2006; OECD, 2001; UNESCO Delors Report, 1996). This definition clearly differentiates lifelong learning from adult learning and further education.

  • In terms of mode of learning, “lifelong learning should encompass the whole spectrum of formal, nonformal and informal learning” (Commission of the European Communities, 2006, p. 3).

  • In terms of objectives of learning, the four objectives suggested by the Commission of the European Communities (2006) are comprehensive and illuminating. Lifelong learning aims to develop and promote active citizenship, personal fulfilment, social inclusion, and employment-related advancements.

  • In terms of learning approaches, self-directed learning, autonomous learning, and self-determined leaning are some of the key approaches that have been widely taken by lifelong learners. The concept of heutagogy has also been advocated as an overarching approach to respond to the needs of lifelong learners (Blaschke, 2012).

  • In terms of underpinning principles, lifelong learning is based on four pillars: learning to know, learning to do, learning to live together, and learning to be (UNESCO, 1996). Learner-centeredness, equal opportunities, and the quality and relevance of opportunities are also principles applied to lifelong learning (European Communities, 2006)

Clearly, lifelong learning is important to everyone and has particular and profound implications for teachers and their professional development. These fundamental tenets of lifelong learning have also informed teachers’ professional growth as lifelong learners. When discussing teachers as lifelong learners, Zhu (2004) pointed out that the changing demands from today’s education made lifelong professional development inevitable if teachers wanted to stay current with the advancements in knowledge and education systems, and if they wanted to be competent and innovative in playing the roles required of them. Furthermore, Tang’s (2006) research indicated that transforming teacher education from the one-off model to lifelong education, and eventually, to lifelong learning largely depended on teachers themselves.

Lifelong learning is much more crucial and urgently needed in TVET. This is because the technological transformation happening in TVET education and workplace requires students and teachers to upgrade their knowledge and skills throughout their life. This is why lifelong learning was clearly articulated in a Strategy for TVET (2016–2021). This Strategy promises support for “the efforts of Member States to enhance the relevance of their TVET systems and to equip all youth and adults with the skills required for employment, decent work, entrepreneurship and lifelong learning, and to contribute to the implementation of the 2030 Agenda for Sustainable Development as a whole”.

2.3.2 Situated Learning

Situated learning is a learning theory that examines the importance of context and culture to learning. Carr et al. (1998) believed that understanding learning required careful consideration of cultural and situational factors, or the behavior and value orientation in the cultural context. Reviewing the literature on situated learning, Carr et al. (1998) synthesized the key beliefs embraced in this learning theory as follows:

  • Knowledge is a product of activity, not a process of acquisition.

  • Learning is a process of enculturation in a community of practice (Brown et al., 1989); Communities of practice are discussed in Sect. 2.3.5.

  • Learning is developing an identity as a member of a community of practice (Lave & Wenger, 1991).

  • Meaning is socially constructed through negotiation.

  • Learning in situ engages different socio-cognitive process than learning in schools (p. 6).

Similarly, to Lave and Wenger (1991) “learning is an integral and inseparable aspect of social practice” (p. 31). This perspective led them to coin the concept of legitimate peripheral participation that explains how newcomers become old timers through participation in a community of practice. Another important concept contained in situated learning is cognitive apprenticeship that emphasizes learning through authentic practices and social interaction (Brown et al., 1989). Section 2.3.4 contains a more detailed discussion on cognitive apprenticeship.

Situated learning has long been adopted in teacher training and professional development in both higher and vocational education. Empirical studies have also established its importance in advancing teacher learning and transferring theory into practice in many significant ways. As far as TVET is concerned, a number of learning/training models and theoretical frameworks have been informed by situated learning theories, for example, the workplace learning model proposed by Illeris (2011). Through a comprehensive review of workplace leaning literature, Zhao and Ko (2018) proposed a workplace learning model specially catering for the needs of TVET teachers’ continuing professional development. This model recognizes the importance of workplace dynamics in developing TVET teachers’ professional identity and competence through situational and practical learning situations. Though still a theoretical framework, the model could be used to facilitate empirical research into TVET professionals’ journey to become “double qualified” teachers who possess both pedagogical/academic expertise and technical abilities (Yu, 2015). In a more general context, Chen (2016) believed that integrating situated learning in teacher education can innovate the process of teacher’ learning and development. Informed by the situated learning theory, she suggested the following strategies to promote teacher education:

  • Transforming teachers’ perspectives on learning through providing opportunities for teachers to engage in authentic task completion in collaboration with industry.

  • Creating communities of practice for teachers to interact with one another.

  • Encouraging teachers to self-manage and self-direct their learning through participation

  • Providing a variety of situated learning opportunities to support teacher development.

Xie and Li (2006) believed that practice and situated learning should be an integral part of teacher education. According to them, one of the reasons for ineffective teacher training was lack of real and authentic training environments. With its emphasis on authentic situations and learner participation, situated learning makes teacher training more effective. Zhou (2017) claimed that with the introduction of the concepts promoted in the situated learning theory, such as situated cognition, legitimate peripheral participation, and cognitive apprenticeships, teacher training in China has been transformed from a “delivery—application” model to a “participation—problem solving” model. Close attention has been paid to the intrinsic needs of teachers that focus on constructing learning communities through encouraging teacher participation and other ongoing professional support mechanisms. In such communities teachers developed new skills, shared ideas, and grew into autonomous learners. Meanwhile, with respect to educational practicum and internship, Yang and Chang (2010) promoted the integration of situated learning with pre-service teacher training during their internship. They observed that many pre-service teachers had experienced a reality shock or praxis shock during their internship by failing to apply the theoretical knowledge learned in the classroom to real teaching situations. Situated learning, to some degree, can help reduce this kind of shock.

2.3.3 Adult Learning Theory

Although developed in the 1970s, adult learning theory still remains the cornerstone of the theories and approaches developed and adopted in teacher education and professional development. As its name suggests, adult learning theory is about how adults learn as opposed to how children learn. It is often used interchangeably with andragogy. In his seminal work, Knowles (1978) proposed the following five assumptions about adult learners based on Lindeman’s (1926) work: (1) intrinsic motivation is important as they feel the need to learn, (2) learning is self-directed as they need to be responsible for their own learning, (3) learning is facilitated and enriched by experience, (4) learning is practical and relevant to their life and work, and (5) learning focuses on problem solving rather than content learning.

In the last 50 years, this understanding of adult learning and learners has given rise to many instructional strategies for fostering each of these assumptions. At the same time, although these key assumptions remain central to the adult learning theory, theoretical development and educational practices have enriched this theory to a great extent. Indeed, as recognized by Merriam (2008), “there is an ever-expanding understanding of what adult learning is and can be” (p. 98). In discussing what adult learning theory encompasses in the twenty-first century, Merriam (2008) proposed that “that adult learning theory is attending more to the various contexts where learning takes place and to its multidimensional nature” (p. 93). An important development of adult learning theory is transformative learning that emphasizes the transformative power of reflecting on one’s existing knowledge and experience (Mezirow, 2000), and making meaning of one’s experience (Merriam & Bierema, 2014).

The adult learning theory has been applied to practices in almost every disciplinary area and has a profound impact on teacher education and professional development. Lu (2010) reported his study on the impacts of adult learning theory on teachers’ competency development and suggested that teachers, being adult learners, have their unique learning characteristics. Accordingly, teacher training should take into consideration the characteristics and principles of adult learning, and explore an effective participatory training model. When discussing the effective development of TVET teachers’ dual role as a teacher and trainer, Peng (2014) proposed a training model that focuses on developing teachers’ competencies for problem solving, teaching innovation, and self-development.

In reference to the key concepts in adult learning theory, such as self-directed learning, experiential learning, transformative learning, Pei and Li (2014) advocated the importance of knowing teachers’ learning orientation, goals, motivation, and approaches. They believed that teacher development should recognize teachers’ self-concept and personal experiences, and stimulate teachers’ intrinsic motivation. These can be achieved through placing teacher development in everyday teaching situations, authentic learning environments, and communities of practice (e.g., in schools, communities, or social circles). Such teacher development can facilitate teachers’ constant self-transformation that also transforms learners in many ways such as knowledge construction, value systems, and disposition.

2.3.4 Cognitive Apprenticeship

Cognitive apprenticeship was first proposed by Collins et al. (1989). It was based on the notion that apprenticeship showed and guided the apprentice on how to do a task until the apprentice was proficient enough to accomplish the task independently (Collins et al., 1991). However, it differs from the traditional apprenticeship in that cognitive apprenticeship focuses more on raising the learner’s awareness of the process of task completion, the contexts of the task, and the wider applicability and transferability of the skills learned. In the words of Collins et al. (1991), in order to translate the model of traditional apprenticeship to cognitive apprenticeship, teachers need to:

  • identify the processes of the task and make them visible to students.

  • situate abstract tasks in authentic contexts, so that students understand the relevance of the work.

  • vary the diversity of situations and articulate the common aspects so that students can transfer what they learn (p. 3).

Collins et al. (1991) further advocated six teaching methods in the context of cognitive apprenticeship. They are modeling, coaching, scaffolding articulation, reflection, and exploration. As Collins et al. explained:

Modeling, coaching, and scaffolding are the core of cognitive apprenticeship, designed to help students acquire an integrated set of skills through processes of observation and guided practice. Articulation and reflection are methods designed to help students both to focus their observations of expert problem solving and to gain conscious access to (and control of) their own problem-solving strategies. Exploration is aimed at encouraging learner autonomy, not only in carrying out expert problem-solving processes but also in defining or formulating the problems to be solved. (p. 13)

Zhong (2008) explained that cognitive apprenticeship addressed the key problems in school education, and integrated the core elements of traditional apprenticeship into school education. Cognitive apprenticeship is premised on the assumption that it facilitates the development of learners’ higher-order thinking skills, and in particular, critical thinking skills and complex problem-solving skills. Zhang and Yang (2005) summarized the following features of cognitive apprenticeship as it:

  • brings more learners’ attention to the process of problem solving, cognitive and meta-cognitive strategies involved in experts’ acquisition of knowledge.

  • makes what is invisible visible in regard to teachers’ or experts’ inner cognitive development. Such visibility makes it easier for learners to observe, model and practice.

  • situates abstract learning prescribed in the school curriculum in meaningful contexts, and connects learning with workplace environments. This allows learners to fully understand the purpose of learning and how they should apply learning to real tasks. This is also a process of modeling the expert’s behaviors.

  • encourages learners to reflect on and clearly articulate the shared principles applied to different tasks, so that learners develop the capacity to apply their knowledge and skills independently to new problem-solving situations.

  • allows the learner to participate in a variety of cognitive activities during the process of completing complex tasks, and externalizing the complex cognitive process through discussion, role playing, and group problem solving. This process will promote the development of meta-cognitive skills, such as self-correction and self-monitoring.

In recent years, teacher training models have been constructed in accordance with the core concepts in cognitive apprenticeship. For example, Hu (2019) adopted authentic tasks, modeling, workshop, and other important elements from cognitive apprenticeship to build a training model for new teachers. This model allowed new teachers to immerse themselves in real classroom teaching contexts and model expert teachers’ behaviors in workshops during the training period. Under the guidance of expert teachers, new teachers gradually developed expertise and tacit knowledge through hands-on learning and real problem solving. This model effectively shortened the time for new teachers to adapt to their new occupations and increased their sense of achievement. Qin and Zeng. (2019) pointed out that cognitive apprenticeship could effectively promote the teaching competencies of young teachers in applied colleges. They also suggested two strategies for developing new teachers’ teaching competence: peer mentoring and teamwork. Chen and Zhang (2009) recognized that cognitive apprenticeship required a smaller teacher-student ratio. When class sizes are small, apprenticeship is easier to manage and learning is more effective. In this case, they proposed to take advantage of today’s technology to achieve small group learning. ICT could support effective mentor–mentee interaction. The use and design of cognitive apprenticeship in online environments have enriched cognitive apprenticeship.

2.3.5 Community of Practice

The concept and practice of Community of Practice (CoP) is not new and has gained popularity since the 1990s. The rapid ICT advancements have also brought a renewed academic attention to this concept in the last 20 years. ICT has empowered CoP in many important fashions, making it more accessible, sustainable, creative, and productive (Dubé et al., 2005; Kietzmann et al., 2013). CoPs are commonly understood as “groups of people who share a concern, a set of problems, or a passion about a topic, and who deepen their knowledge and expertise in this area by interacting on an ongoing basis” (Wenger et al., 2002, p. 4). In the same vain, Pór (2004) defined CoPs as “self-organizing and self-governing groups of people who share a passion for the common domain of what they do and strive to become better practitioners” (p. 7). Pór also pointed out that together members in CoPs “create value for their members and stakeholders,” develop and spread “new knowledge, productive capabilities,” (p. 7) and foster innovation.

While Jameson et al. (2006) highlighted the importance of building trust, knowledge sharing, and collaborative leadership in online CoPs, Zhong and Zhu (2011) stressed the participatory nature of CoPs in terms of co-creation of knowledge and community identity. CoPs are sometimes used interchangeably with terminologies such as learning communities and communities of interest. However, “the sentiment of the CoP model as a collaborative learning experience has permeated the breadth of approaches used” (Pedersen, 2017, p. 685).

CoPs have become an established conceptual lens and strategy for teachers’ professional development and lifelong learning. Their facilitative quality of fostering continued professional development has been confirmed in terms of collegial support, cross-disciplinary collaborative learning, and sustained professional development efforts (see Kong, 2018; Perdersen, 2017; Sterrett et al., 2015). Cai (2021) discussed the possibilities of building a university—primary–secondary school teachers community, to explore issues such as internal culture-driven mechanisms, trans-disciplinary interaction, collaboration, and structural dynamics of CoPs.

In recent years, a range of technologies, in particular, social media and online platforms, have been adopted in the support of teachers’ collaboration and interaction within CoPs. For example, Kong (2018) reported a study on the use of WeChat group as a venue for ESL (English as a Second Language) teachers’ professional development in TVET. Findings from this study indicated that WeChat effectively facilitated the communication and interaction among their CoP members.

2.3.6 The Interconnected Model of Professional Growth

The importance of understanding the process of teacher professional growth and the interrelated factors that foster the process has long been recognized in research and practice. Models for explaining such a process have been acknowledged and/or explored by a number of research studies (see Cobb et al., 1990; Fullan, 1982; Guskey, 1986; Johnson & Owen, 1986; Lappan et al., 1988). Among them, Guskey’s (1986) model of teachers’ professional change had a substantial impact on models developed subsequently. This model emphasizes a linear sequence of change in teachers’ beliefs and attitudes preceded by change in teachers’ classroom practice and student learning outcomes. Reflecting and expanding the three domains of changes, Clarke and Peter (1993) proposed the Interconnected Model of Professional Growth (hereafter, the Interconnected Model), which was later further developed by Clarke and Hollingsworth (2002). Different from Guskey’s model, the Interconnected Model constituted four domains, namely, the personal domain (teacher knowledge, beliefs and attitudes), the domain of practice (professional experimentation), the domain of consequence (salient outcomes), and the external domain (sources of information, stimulus or support). What made this model different from Guskey’s was its emphasis on the interconnectedness (non-linear) of the four domains and the mediating agents of these changes (i.e., reflection and enactment). The model suggested change occurring in one domain led to change in another through the mediating processes of reflection and enactment. Another feature of the Interconnected Model that distinguishes it from other models was its recognition of “professional growth as an inevitable and continuing process of learning” with “multiple growth pathways between the domains’’ (Clarke & Hollingsworth, 2002, p. 951).

The Interconnected Model has been widely applied to studies and practices exploring teacher change (Boylan et al., 2018; Chan et al., 2019; Goldsmith et al., 2014; Justi & van Driel, 2006). It has also informed the design and development of many teacher professional development programs (Boylan et al., 2018). The study by Jin et al. (2021) was a case in point. This study investigated the effectiveness of novice-expert interaction on the professional development of TVET teachers in China. The Interconnected Model was adopted in this study to better understand what ways the external domain, in their case the support from expert teachers, impacted novice-teachers’ personal domain, domain of practice, and domain of consequence. Their findings suggested that expert teachers’ feedback and suggestions constituted an important external stimulus to encourage and sustain novice teachers’ professional learning.