Introduction

Differentiated instruction (DI) has received considerable scholarly attention in recent years (Bondie et al., 2019; D’Intino & Wang, 2021; Wan, 2017). DI plays a crucial role in catering for learner diversity, which is a fundamental educational issue around the globe (Griful-Freixenet et al., 2021; Sharp et al., 2020). Through tailoring instructional approaches to the individual needs and interests of students from various backgrounds, every learner can find their own path to success. However, research suggests that teacher professional development in DI remains insufficient (D’Intino & Wang, 2021; Wan, 2017), posing a formidable challenge to effective DI implementation in classroom settings. Teacher professional development or professional learning has also attracted sustained research attention, since teachers play a crucial (or even the most important) role in affecting school quality and student learning (Sancar et al., 2021). Different models have been proposed (e.g., Opfer & Pedder, 2011; Sancar et al., 2021) to understand the process of teacher professional development and its mediating factors. The consensus among recent models is that teacher professional development is a complex, dynamic and multidimensional process (Clarke & Hollingsworth, 2002), with teachers’ characteristics being an important dimension to consider. Sancar et al. (2021) discuss the interplay of teachers’ professional features (e.g., experience, beliefs, knowledge, self-efficacy), individual features (e.g., language skills, higher-order thinking skills) and external variables (e.g., school contexts, policies and supporting activities) in mediating the relationship between teacher professional development and classroom practices. The teachers’ characteristics can be better captured with the notion of teacher empowerment, which can be defined as a process in which teachers develop the competence and confidence to take charge of their own growth and resolve their own problems (Rinehart et al., 1998). Previous research has shown a reciprocal relationship between teacher professional development and teacher empowerment. That is, teacher empowerment can be facilitated by professional development programmes or activities (Fang et al., 2004), while teacher empowerment can serve as a key drive for professional growth (Tannehill & MacPhail, 2017). Hence, an in-depth understanding of the teacher empowerment process can shed light on teachers’ enhancement of autonomy and self-efficacy and the sustainability of professional development programmes.

This article reports a case study examining a group of in-service teachers’ journey towards empowerment in DI, with a view to conceptualising a model for sustainable teacher professional development. The findings suggest a three-stage journey towards teacher empowerment in DI and reveal the factors influencing the journey. The study represents a pioneering attempt to undertake a longitudinal analysis of how teachers were empowered to develop their professional capacity in catering for learner diversity. While a recent meta-analysis of research studies on professional development in DI has been conducted (i.e., Kahmann et al., 2022), this study incorporates several of Smets and Struyven’s (2018) recommendations for research design on DI, such as utilising open systems and researcher reflectivity. Accordingly, this study fills the gap in comprehensive data collection on professional development and teacher empowerment in DI, an area Smets and Struyven (2018) identified as lacking depth. It also contributes to the field of teacher education by advancing our knowledge of how teacher capacity in implementing DI can be enhanced.

Conceptual framework

Differentiated instruction

The increasing diversity of students’ academic backgrounds, learning profiles, motivation, skills, races and family support poses a challenge to the one-size-fits-all pedagogical approach in meeting the wide array of learner needs. DI is regarded as a useful approach to accommodating learner diversity (Tomlinson, 2014). This approach respects individual differences and recognises the potential of each learner to maximise academic growth when instruction and curriculum are tailored to students’ readiness, interests and learning profiles (Tomlinson, 2014). Rather than providing an individual programme for each student (Goodnough, 2010), teachers differentiate instruction by establishing a supportive learning environment, offering choices in learning content and materials, adopting flexible groupings for classroom activities and providing timely and contingent formative feedback on student work (Tomlinson & Moon, 2013).

DI implementation requires teachers’ careful designs of learning environments, curricula, assessment, instruction, and classroom management to engage students with varied learning profiles and needs (Tomlinson, 2014; Tomlinson & Moon, 2013). DI implementation encompasses four dimensions: learning environment or affect, content, process, and product (Tomlinson & Moon, 2013). Learning environment or affect refers to a classroom climate conducive to all students’ participation. Content comprises the teaching and learning materials and resources students need to grapple with. Process is how students arrive at a thorough understanding of the learning content. Product refers to the ways students demonstrate their understanding and attainments.

In our study, three major DI strategies within Tomlinson and Moon’s (2013) framework were introduced to the teacher participants. First, teachers set tiered learning goals for students with different readiness levels. For instance, for vocabulary learning, students with higher English proficiency were expected to recognise and apply all target words in various contexts, while those with lower English proficiency recognised all target words and applied most in a given context. Second, teachers used tiered worksheets (i.e., worksheets with different versions for students with varying levels of readiness, language proficiency, or skills) to meet diverse needs and help students achieve goals. Third, through multi-sensory pedagogical designs, teachers engaged students’ different senses (e.g., sight, hearing, touch) to facilitate learning. For instance, they used sounds and visuals to elicit responses from students with varying learning preferences.

Challenges in DI implementation

The variety of instructional arrangements places pressing demands on teachers to become well-versed in the conceptual principles and practical strategies of DI. To meet the growing need for teacher professional development in DI, educational authorities worldwide have taken initiatives to upskill teachers for DI implementation. For example, South Korea’s SMART education initiative equips teachers with strategies to address learner diversity (Cha & Ahn, 2014). With the aim of promoting DI, the ability to implement DI is included as one of the criteria to assess teacher competence in Belgium (EC, 2015), Britain and Australia (Mills et al., 2014). In-service training, like Hong Kong’s Basic-Advanced-Thematic courses and Taiwan’s 6 day inclusive education programme, aids teachers in identifying student needs and implementing DI strategies (Legislative Council Secretariat, 2019).

Despite the efforts in increasing teachers’ DI implementation skills, some teachers lack confidence and capabilities in practice (Wan, 2017). Chan and Yuen (2015) discovered that the practitioners in their case study school still held the misconception that individualised materials should be developed for diverse learners after the completion of professional training. Brighton et al. (2005) and Wan (2017) found that in a large class setting some teachers mainly offered remedial support to struggling learners in a mixed-ability class while failing to extend the learning potential of students with higher levels of readiness. Suprayogi et al. (2017) revealed a lack of professional development programmes focusing on DI and called for more attention to this issue in order to enhance teachers’ capacity to implement DI. The empirical studies seemed to suggest that teacher professional development may not be adequate or effective in honing teachers’ DI implementation skills.

Models of teacher professional development

Different models of teacher professional development have been presented in the literature. Earlier models (e.g., Guskey, 1986) tend to portray teacher professional development as a linear process: teachers receive training and then change their knowledge, beliefs and classroom practices, which in turn may affect student outcomes. There has been some debate about whether teachers would change their beliefs before or after changes in student outcomes. However, regardless of the sequence of change, these models are still depicted as linear and grounded on a deficit-training-mastery mindset (Clarke & Hollingsworth, 2002).

The linear model of teacher professional development has been gradually replaced by models that underscore the cyclic, dynamic and complex nature of teacher professional development. For example, Clarke and Hollingsworth’s (2002) Interconnected Model of Teacher Professional Growth comprises four domains, namely external domain, personal domain, domain of consequence, and domain of practice. This model emphasises the interconnection of the four domains through the mediating processes of teachers’ enactment and reflection. Changes in any one of the domains (e.g., professional development activity in the external domain) will possibly lead to changes in one or more of the other domains (e.g., experimentation with a new strategy in the domain of practice; recognition of the impact of the new strategy on student in the domain of consequence; change of knowledge and beliefs in the personal domain). The model further differentiates “change sequences” (short-term change) and “growth networks” (long-term change). While most professional development programmes or activities will result in some changes in the four domains, not all of them will lead to lasting changes in teachers’ practice, knowledge or beliefs. Hence, effective professional development programmes should facilitate the transformation of short-term change sequences to more lasting growth networks.

The four domains in Clarke and Hollingsworth’s (2002) model largely echo the three recursive systems (the teacher, the school and the learning activity) in Opfer and Pedder’s (2011) model. Here, the teacher subsystem encompasses teachers’ existing knowledge, beliefs, practices and past experiences, which all constitute a teacher’s “orientation to learning”. Such orientation then interacts with the professional learning activity (e.g., how teachers welcome or resist the professional learning activity) and the characteristics of the school context (e.g., the school beliefs and norms of actions may shape individual teachers’ orientation to learning). Based on a review of 156 articles on teacher professional development, Sancar et al. (2021) developed a comprehensive conceptual framework to construe teacher professional development as a lifelong process starting from teacher education programme and continuing till the end of professional career. This ongoing process is mediated by a series of external variables (e.g., reforms and policies, curricula, supportive activities, collaboration, school context) and variables related to classroom practices (e.g., teacher characteristics, what to teach, how to teach, and students’ learning outcomes). Here, “teacher characteristics” comprise professional features (e.g., professional experience, competence, beliefs, confidence, knowledge) and individual features (e.g., language skills, critical thinking), and they form part of “classroom practices”.

Despite some differences in the recent models of teacher professional development, their common proposition is that teachers bring along their experience, knowledge and beliefs to professional development activities and constantly reflect on their experience (Clarke & Hollingsworth, 2002; Opfer & Pedder, 2011). Particularly, teacher agency plays an indispensable role in shaping teacher professional development. Agency can be conceptualised as the way actors “critically shape their responses to problematic situations” (Biesta & Tedder, 2006, p. 11). It can be achieved under specific contextual configurations (Priestley et al., 2013) through the dynamic interplay among personal efforts, existing resources, and structural factors (Biesta & Tedder, 2007). It is worth further exploring how teachers’ personal characteristics and agency may shape or be shaped by their professional development.

Teacher empowerment and professional development

As reviewed above, teachers’ important role during professional development has been discussed in different ways and quite a few characteristics, including beliefs, knowledge, self-efficacy, attitudes, anxiety, motivation, skills, competency and practice, have been highlighted (Sancar et al., 2021). Perhaps these different aspects could be captured by the notion of teacher empowerment, which is defined by Rinehart et al. (1998) as “a process whereby school participants develop the competence to take charge of their own growth and resolve their own problems” (p. 635). Teacher empowerment consists of six key dimensions including (1) teachers’ participation in work-related decision-making, (2) teacher impact being perceived as an important indicator by school management, (3) professional respect gained from their colleagues, (4) autonomy or beliefs in their work life, (5) opportunities to achieve continuous professional development, and (6) self-efficacy (Short, 1992). A number of empirical studies conducted within the last two decades (e.g., Balyer et al., 2017; Fang et al., 2004; Zembylas & Papanastassiou, 2005) have suggested that teacher empowerment can be achieved through professional development. For instance, Fang et al. (2004) reported a longitudinal professional development project which supported teachers to become empowered professionals. Through monthly meetings during the project, the teachers changed from relying heavily on outside experts and commercial programmes to making independent decisions based on their own professional judgement. In another study, Zembylas and Papanastassiou (2005) revealed that teachers’ job satisfaction with professional growth can contribute to their sense of empowerment. Further, Balyer et al. (2017) found that school administrators were crucial in supporting teacher empowerment, but they did not provide sufficient support in this respect.

While the above literature suggests that professional development can lead to teacher empowerment, other empirical research indicates that teacher empowerment can in turn impact on professional development. For instance, Lee et al. (2011) suggested that teacher empowerment could improve teachers’ sense of professionalism which in turn enhanced their teaching performance. Drawing on Short and Rinehart’s (1992) six dimensions of teacher empowerment, Tannehill and MacPhail’s (2017) findings demonstrated how status, autonomy and impact contributed to teacher professional development, which suggested that teacher empowerment was a key drive for professional growth. Most recently, Gonçalves et al. (2020) highlighted the importance of teacher empowerment in professional learning communities. They suggested that teacher empowerment could help teachers improve their professional knowledge and conditions.All these studies seem to imply a reciprocal relation between teacher empowerment and professional development.

Research gaps and questions

While the prior scholarship has indicated a potential interplay between teacher empowerment and professional development, the pathways and journey towards teacher empowerment in the context of professional development are underexplored. A nuanced understanding of these issues is crucial because it could help to identify the potential mediating factors that impact on teacher empowerment and construct a sustaining model for teacher professional development. Our study features a qualitative research design, addressing the lack of in-depth data collection on teacher professional development and empowerment in DI. Hence, this qualitative inquiry seeks to provide a thick description of the journey towards teacher empowerment in a DI-related professional development programme. The research questions are as follows:

  1. 1.

    How are teachers empowered to plan and implement DI in a teacher professional development programme?

  2. 2.

    What are the factors influencing teacher empowerment?

Method

Context and participants

This study was from a 2 year longitudinal school-university teacher professional development project with the aim of providing 11 schools with pedagogical support for catering for learner diversity. This paper reports the findings from one of the schools, with a particular focus on the developmental trajectory of English teachers. This school was selected for in-depth investigation for three reasons. First, this publicly funded primary school in Hong Kong had a heterogenous student population comprising students with special educational needs, Chinese and non-Chinese speakers. The diversity in readiness level, skills and ethnicity posed a challenge for the school to address students’ needs effectively. Second, the School Principal was enthusiastic about catering for learner diversity and offered teachers different kinds of resources and support for DI implementation. This cast light on the school management’s influence on the teachers’ professional development journey. Third, the wide range of teaching experience of the participating English teachers (presented in Table 1) represented different levels of engagement and progress in this professional development project.

Table 1 Information of the seven participating English teachers
Full size table

This study involved seven female teacher participants whose teaching experience ranged from 22 to 2 years (see Table 1 for details). Three of them (Mary, Amy and Elaine) joined the project for 2 years (September 2019 to August 2021). Two (Mabel and Carol) left the project after the first year because the Principal assigned them as the “seed teachers” to share their DI experience and related pedagogical skills with the English teachers at two other grade levels in the second year. This arrangement aimed to make the project sustainable and scalable in the long-term. The other two teachers (Jamie and Sammy) participated in the project to replace Mable and Carol. Each participant in the first year taught a class of primary two students (equivalent to Grade 2), and Mary, Amy and Elaine kept teaching the same class when the students advanced to primary three in the second year. Jamie and Sammy took up the classes of Mabel and Carol in the second year.

Pedagogical support to teachers

The school-university collaboration involved pedagogical support from a curriculum consultant (pseudonym: Susan) of a university in Hong Kong. Susan was a doctoral degree holder with substantial experience in English language teaching and curriculum design and a good understanding of Hong Kong’s education system. She developed her expertise in DI from her prior experience as a teacher and the Deputy Panel Head of English Language in a secondary school, and more importantly from working with different frontline English teachers in a range of professional development projects. She assisted the teachers in designing teaching packages and implementing DI in their respective classes through four types of support.

First, two 1 hour workshops were delivered to familiarise the teachers with the DI approach. The first workshop introduced the dimensions of learning environment or affect, content, process and product and shared examples of DI implementation. For instance, under the content dimension, tiered worksheets were shown to explain how different versions of a worksheet could be designed to meet the needs of students with varying levels of readiness and interest. Under the process dimension, the multi-sensory pedagogical approach was demonstrated to exemplify the use of sounds, visuals and touch to reinforce students’ learning. These principles were discussed because the teachers lacked a clear understanding of DI and ways to incorporate tiered worksheets and the multi-sensory approach into regular teaching. The second workshop focused on the development of DI assessment tools as the teachers lacked skills to apply DI in tests and other assessment events. A test paper with student’s answers and its marking scheme were utilised to clarify how questions could be set to differentiate students’ proficiency levels and how to use assessment data to support students’ learning in subsequent lessons.

Second, lesson co-planning meetings were held fortnight in each semester for Susan and the teachers to co-develop pedagogical plans and materials for DI implementation. Prior to the meetings, the teachers produced a draft of pedagogical materials for Susan to comment. The materials usually included lesson plans and tiered worksheets to cater for students’ diverse readiness and language proficiency levels. During the meetings, they explained their material designs, followed by Susan’s suggestions on how to improve their designs and strategies to implement DI in classroom activities. For example, when Susan found different versions of the tiered worksheets unable to provide adequate support for students with diverse needs, she showed the teachers tiered worksheets developed by other project schools to stimulate their thinking and reflection. With reference to those materials and formative assessment data (e.g., students’ answers to the questions on the tiered worksheets), they revised their lesson plans and materials and discussed the revised materials in the following meeting. Each meeting lasted for approximately 70 min in the first project year and 90 min in the second year.

Third, lesson trials were conducted by individual teachers to demonstrate a DI strategy of their own choice to Susan and the other participants. Before lesson trials, all lesson observers were informed of the DI strategy to be demonstrated and provided with the set of pedagogical materials discussed in co-planning meetings. During lesson trials, Susan and other teacher participants would examine the extent to which the DI strategy was applied effectively to cater for learner diversity. To encourage an open discussion of pedagogical effectiveness, there was a post-lesson observation debriefing session for the observed to reflect on the teaching practice and the observers to consider alternative ways of lesson implementation. To stimulate the teachers’ reflections and sharing, Susan would provide general comments on the lessons first and then raise questions for them to ponder. She would also advise them on DI implementation based on students’ classroom performance and praise them for successful implementation of DI strategies if she observed that most students meaningfully engaged in their learning tasks.

Fourth, a professional development circle was established for the teachers to exchange pedagogical ideas with those of other participating schools at the end of the first year. In the meeting, the teachers presented their developed materials to the circle of friends, learnt from others’ DI experience and derived insights into DI implementation and designs.

Data collection and analysis

Case study was adopted for our research design because it investigates “a contemporary phenomenon (the ‘case’) in-depth and within its real-world context” (Yin, 2018, p. 45). This design helped us address the “how” and “why” questions regarding teachers’ empowerment. According to Yin (2018), case study draws on multiple data sources, and one dominant technique for data analysis is explanation building. In this study, three major sources of data were collected and analysed to explore the participants’ journey towards teacher empowerment and possible factors influencing their journey.

First, 23 lesson co-planning meetings were observed and audio-recorded to trace the teachers’ changes in participation and involvement. The first two authors participated in the meetings as non-participant observers, taking field notes about consultant-teacher interaction and instances signaling teachers’ responsibility for professional growth (e.g., leading the discussion). Dialog excerpts that demonstrated teacher empowerment were transcribed and subjected to a comparative analysis. Following Rutakumwa et al.’s (2020) procedures of conducting a comparative analysis, the first author compared and contrasted different excerpts with a focus on the consultant’s and teachers’ roles in leading the meetings. Such an analysis constituted an integral part of the explanation building.

Second, semi-structured teacher interview data were gathered at the beginning of the project (i.e., August 2019) and the end of first and second project years (i.e., June 2020 and June 2021), with the goal of exploring the teachers’ perceived change in the ability to cater for learner diversity and possible factors explaining teacher empowerment. Generally, they were prompted to reflect on their gains after receiving professional support. During the interviews in June 2021, they were specifically asked about their change from the first co-planning meeting to the final one. All interviews were carried out in their native language, Cantonese, to avoid language barriers. Each interview took around 30 min. Due to COVID-19, all interviews in 2020 and two in 2021 were conducted via Zoom (an online conferencing tool). The interviews were audio-recorded and transcribed, followed by a manual line-by-line thematic analysis (Braun & Clarke, 2006). Inductive coding was first undertaken to generate descriptive codes (e.g., joined the co-planning meetings to receive suggestions; teachers became more proactive to share their thoughts) that could summarise the interviewees’ responses for subsequent categorisation. Similar codes (e.g., improved readiness for DI practice; actively leading co-planning meetings) were then assembled into provisional themes (e.g., improved agency and initiative). Continuous reflections by the first author were undertaken to make sure that all provisional themes were associated with the research questions and supported by convincing data from the interviewees. Afterwards, the themes were compared and combined to produce the main themes based on which the researchers constructed analytic narrative of the data.

Third, 18 lesson trials were observed and video-recorded between December 2019 and June 2021 to examine how the teachers implemented the DI strategies discussed in the co-planning meetings. Each lesson lasted approximately 35 min. The 18 post-lesson observation debriefing meetings were observed and audio-recorded to see how the curriculum consultant guided their reflections on teaching. Each meeting took approximately one hour. We jotted down field notes about the teachers’ effectiveness of DI implementation during the observations and debriefings. We then conducted the thematic analysis to analyse the field notes. Similar codes (e.g., reflections on the strengths of classroom activities; reflections on the weaknesses of classroom activities) were assembled into provisional themes (e.g., teachers’ reflections on teaching effectiveness). In this sense, such a thematic analysis also contributed to the explanation building of the case study.

To safeguard the trustworthiness of the findings, several methods were used to enhance credibility, transferability, and confirmability (Cypress, 2017). Credibility was achieved through methodological choices of the study. The use of multiple data collection methods afforded the collection of thick and rich data from the teacher participants. Member checking was conducted to accurately record their intended perspectives. For transferability, we provided a holistic description of the research context and participants as well as data collection and analysis procedures. Confirmability was achieved through being upfront about our biases by virtue of regular discussions among all the authors and reflections on the data collected and its possible interpretations.

Reflexivity statements

As a cornerstone of insightful qualitative research, reflexivity acknowledges the potential impact of one’s own bias, subjectivities, and judgement systems on the research throughout the entire research process (Jamieson et al., 2022; Olukotun et al., 2021). The first author served as a postdoctoral researcher collecting and analysing data to evaluate the impact of the project on different stakeholders. With fundamental theoretical knowledge but little practical experience in DI, he strived to hold a balanced view on the data collected by considering different stakeholders’ perspectives from multiple data sources. He had regular meetings with the third author to report his observations of various aspects of the project as a non-participant observer, including the teachers’ professional growth. Through such timely and thoughtful discussions, he constantly reflected on his role throughout the project and brought unchecked assumptions to the surface.

As a researcher with 7 year teaching experience at school, the second author had a basic understanding of DI and some experience of implementing the multi-sensory pedagogical approach. To manage subjectivity in the research process, she took a non-participant role during lesson co-planning meetings, lesson trials and post-lesson observation debriefing sessions and refrained from commenting on teachers’ responses during the interviews. When analysing data, she discussed with the research team how her prior teaching experience had shaped her data interpretation.

Findings

We present the findings according to the research questions. The teachers’ transformation from passive participation to active involvement is depicted in three key stages, followed by the examination of the factors influencing teacher empowerment.

Journey of teacher empowerment

Stage 1—passive learning

At the outset of the project, all teachers were rather passive, expecting to receive help and advice from the university consultant during the lesson co-planning meetings, as Elaine revealed in the interview: “At the beginning our roles were mainly participants … During the first year, we relied on Susan’s ideas on how to design lesson plans”. At this stage, the consultant and all teachers seemed to have unequal status, with the former leading the meetings and the latter heeding the given advice. As the typical interaction pattern in the first few co-planning meetings, the following excerpt from the fourth meeting exemplifies the characteristics of the interaction between Susan and the teachers.

Susan: [commenting on the worksheet for students with higher English proficiency and providing suggestions] This method also works, as students do not need to fill in too much information, but the order of the questions needs to improve … If you want to have three different versions of the worksheet, you can think in this way … [teachers were listening and jotting down notes] This is based on the assumption that students with higher English proficiency have already understood the lesson, which is a very good practice.

Mary: This is actually developed with reference to the scheme of work.

Susan: The school should make good use of this high quality stuff and not waste it.

[Silence for around 40 seconds]

Susan: I will help you further revise the learning objectives.

Mary: Okay.

Susan: Well, how many lessons should this need?

Mary: Around two lessons.

Susan: This part should be cut… [teachers listened attentively to Susan’s explanation]

Mary: Maybe the second reading.

Susan: You mean the part for introducing the text type?

Mary: Yes, or the second lesson for the text type, or the first lesson would end after doing the first reading, right? But how about adding the text type to the second reading? Would this be too much?

Susan: If page 1 and page 2 are covered in the first lesson, then actually you give students time for reading. You lead them to read each slide and stanza and leave some time for them to do individual practices. The content of such a lesson should be enough.

Mary: I agree. [Susan continues to advise teachers on how to teach the reading of the poem].

In this excerpt, the consultant provided the teaching team with suggestions on how to use the tiered worksheets and raised questions about the number of lessons required for worksheet completion. The most experienced teacher (Mary) interacted with Susan on behalf of the team and expressed agreement most of the time. The other teachers mainly took notes and seldom raised questions. There was a moment of silence when the team did not know how to respond to Susan’s comment on the use of worksheets and waited for Susan’s explanation. At the end of this co-planning meeting, Susan expressed her disappointment to the researchers as most of the teachers were awaiting her spoon-feeding most of the time and did not send her their designed materials for comment prior to the meeting. This excerpt seemed to imply a lack of active teacher participation and co-construction of DI strategies at the early stage of the project.

Stage 2—active engagement

The situation improved after the fifth meeting when Susan required all teachers to upload their designed materials and lesson plans to a Google shared folder two days in advance, with a view to improving their readiness for the meetings. At the beginning of the meeting, she explained her multiple roles to the team: as a knowledge provider to enlighten the team about DI principles; as a facilitator to guide their materials design; as a coach to improve their DI implementation skills. She also encouraged all teachers to voice their views and concerns about DI implementation. Since then, they participated more proactively and confidently in the co-planning meetings. Mary and Amy took a direct role to lead the team discussion. Mabel, Elaine and Carol actively articulated their students’ learning difficulties and sought advice from Susan for DI implementation. The following excerpt from the ninth co-planning meeting captured how Amy led the discussion on how many versions of worksheets should be designed for students of varied English proficiency.

Susan: How many of you are fine with this arrangement? All three versions of the worksheets look good. I will give the easiest one to the weakest students.

Mary: I think this can help most students, but of course this will make the distributing process more complex, as there are three types of students now. Usually the classroom learning assistant distributes worksheets to students with higher English proficiency while I distribute worksheets to students with lower English proficiency. But there is a way to streamline this process by marking down students’ names on the versions of worksheets they will receive. But if you think there is no need for so many versions of worksheets, then it is fine, too. Or do not give them the “Heart Version”Footnote 1of the worksheet to see if students with lower English proficiency can still write something down and finish the “Sun Version”1 of the tiered worksheets.

Amy: How about all of us sharing our opinions on whether we should keep two versions or three versions? Then explain why so that we could have more exchange of ideas.

Elaine: There are a few concerns. Firstly, usually there are only two versions, so maybe keeping it this way can make it easier for us and students to follow. I am thinking if we should add a version of tiered worksheet with given words and another version without such words, so that students can practise word spelling. When they find out they do not know how to spell the words as they do the worksheets, they may have the incentive to look them up in their textbooks. But on the other hand, if the learning focus is on grammar, providing them with the vocabulary items can make students focus on what they are going to learn. So I guess both versions have their own merits.

Mary: Assuming the two versions of tiered worksheets provide the word spelling, should we include the “-s” and “-es” in the spelling as well?

Elaine: I think we can omit them. Because they are one of the grammar points that we want students to learn later. Of course, I think they will be challenging for the students.

Mary: How about other colleagues?

Carol: I agree with Elaine. Having two versions is fine. Because, normally during a lesson, when we distribute the worksheets, the students who are assigned the “Star Version” would say, “Oh, I want to do the ‘Heart Version’ instead.”

Compared with the meeting excerpt in Stage 1, this excerpt features more interactions among most of the teachers. Mary was able to analyse the advantages and disadvantages of using three versions of tiered worksheets and propose coping strategies to deal with the potential problems. Amy invited her colleagues’ views on the number of worksheet versions. Elaine pinpointed that the design of worksheets and the provision of scaffolding to students should align with the lesson objective. Carol justified her opinions in consideration of her students’ learning preference. In general, their dialogue indicated that the teaching team gradually developed their understanding of tiered worksheet design and critically pondered the DI implementation in their own teaching context under the consultant’s continuous guidance. This signals their active engagement and increased confidence in the professional development project.

Echoing the findings from the excerpt, the interview data suggested that the majority of teachers boosted their confidence in expressing views in the co-planning meetings because of their senior colleagues’ encouragement. They seemed to experience professional growth with the aid of strong collegial support. This can be illustrated by Amy’s interview responses, “Of course I think it is crucial to give some encouragement. After the first few co-planning meetings, I had informal chats with my colleagues and encouraged them by giving credits to their thoughts and ideas. I believe this helped to boost their confidence because after all, the other three colleagues were relatively novice except me and Mary”.

Stage 3—development of agency and independence

This stage was characterised by teachers’ improved agency and decision-making ability in their professional growth. Reflecting on the transformation they experienced throughout the co-planning meetings, the majority of participants agreed that they improved their agency and initiative as the project unfolded, as Jamie reflected, “My biggest change from my initial participation to this moment is my improved initiative. At the beginning, Susan gave us a lot of ideas about how to help students with diverse English proficiency in different lessons like vocabulary, grammar, and reading lessons. Later on, our teachers adapted the ideas according to the practical conditions or the students’ readiness levels or the activities they need.” This quote indicates that most teachers developed their agency in the sense that they actively responded to problematic situations (i.e., adapting Susan’s ideas according to the practical conditions) (Biesta & Tedder, 2006). It seemed that such enhanced agency was achieved as a result of their individual efforts (e.g., co-planned lessons with Susan), available resources (e.g., Susan’s ideas and suggestions), and contextual factors (e.g., “the practical conditions or the students’ readiness levels or the activities they need”) (Biesta & Tedder, 2007).

Such improved agency and decision-making ability are also evident in the following excerpt from the 20th co-planning meeting in which most teachers participated in a discussion to actively address the needs and challenges for students with different English proficiency when compiling a vocabulary list.

Amy: We can teach “glue stick” and “sticky tape”. I think “stick” is quite similar to “sticky” and hope to help students learn their spelling. I remember our Native English Teacher usually uses these phrases when teaching words like “glue.” May I know your suggestions please?

Mary: The word “scissors” can also be taught to students because they frequently use this word but do not know how to spell it. Or would this word be too difficult so we should not teach it to students? I am really concerned about that as they frequently use this word but have the wrong spelling.

Sammy: I think the word “scissors” would be a bit difficult for students with lower English proficiency. This is because of its pronunciation and spelling. This word contains the letters “s” and “c” which are similar to each other, and this could be difficult for students with lower English proficiency. So I think the six selected target words are appropriate for students with different English proficiency. I am just thinking whether other words could also be included into the target word list.

Mary: Last time Susan also mentioned this word, and she said that even secondary students would spell it wrong. Considering this, should we let students practise its spelling more? But of course, even if we do not put it in the target word list, students with higher English proficiency can still learn this word. I am thinking it might be good to let students know this word since it is very difficult. May I know your ideas?

Elaine: I think putting this word in the target word list would pose a challenge for students with lower English proficiency. I agree that this word is relatively difficult for them. But maybe we can encourage students with higher English proficiency to spell it in class. I remember Susan once suggested designating a corner of the blackboard for the vocabulary targeted at students with higher English proficiency. Whenever they finish their tasks ahead of time, they can be asked to spell those difficult words on the corner.

In contrast to the excerpts illustrating Stage 1 and Stage 2, this excerpt demonstrated that the majority of participants were able to initiate and sustain meaningful discussion on DI. Amy first explained why “glue stick” and “sticky tape” should be taught to students and then encouraged others to share their views, followed by a range of opinions on whether and why the word “scissors” should be included in the target vocabulary list. During the discussion, they applied the DI strategies they had learnt from Susan in previous meetings and developed the vocabulary list without Susan’s input. Since they demonstrated independence in decision-making, Susan rounded up the discussion with some positive comments to show her appreciation.

Teacher empowerment also manifested itself in the teachers’ reflections on their DI implementation. In the last post-lesson observation debriefing session, all teachers reflected on the effectiveness of the DI strategies they had tried out in the lessons observed. They discussed how the implementation of the strategies could be further improved, suggesting that they experienced a reflective process in professional development at this stage. In particular, they discussed the effectiveness of the “Buyer and Seller” game (a vocabulary activity requiring students to listen to teacher’s instructions and pick the described items from a bag). Without any input from Susan, Mary (the observed teacher) reflected that students sitting at the back of the classroom did not participate well because they failed to understand her instructions and fetch the objects. She said she should have let those students who needed more support sit in the front of the classroom so that they could seek help from their peers sitting at the back and completed the activity together. Her reflections also reminded the other teachers of the seating arrangements of students with different levels of readiness when implementing a DI activity.

Factors influencing teacher empowerment

While 4.1 depicts the developmental stages of teacher empowerment, it is insightful to understand what mediates the processes of teacher empowerment because such understanding can help to conceptualise a teacher professional development model containing different parameters and variables. This will further enhance the significance of the present study since by attending to the variables, scholars and practitioners can promote teacher empowerment in different contexts. In the present study, two possible factors affecting teacher empowerment were inferred from the data.

External professional support

The first type of external professional support was from the university consultant at different levels. At the epistemological level, Susan provided all teachers with conceptual and procedural knowledge of DI in the workshops, co-planning meetings and post-lesson observation debriefing sessions. Her role as a knowledge provider was crucial at the initial stage of the project as half of the teachers in the subject team possessed less than 4 years of teaching experience. As mentioned by Jamie in the interview, “the classroom experience and knowledge of how to effectively use the DI strategies in class to help students” provided by Susan were crucial. Susan’s explanation of DI principles and demonstration of DI strategies in the meetings enhanced their DI understanding.

At the training level, Susan’s scaffolding in the meetings and debriefing sessions gradually faded when the teaching team was gaining more understanding of DI and confidence in DI implementation. In the co-planning meetings in the second project year, she encouraged all teachers to assume more responsibility and control of their own professional development so that their growth could sustain even after the project ended. She also stressed the importance for them to exercise autonomy and apply DI knowledge without too much guidance from her. It turned out that most teachers became more active and played a leading role in the meetings. This point was raised by Elaine in the interview “I think Susan’s design is excellent. She gives us more and more trust while slowly reducing her participation, which allows us more space for our own discussion”.

At the knowledge exchange level, Susan formed a professional learning circle to allow the teaching team to gain inspirations from the pedagogical sharing of other project schools. This was evident in the first co-planning in the second project year in which Amy, Mary and Elaine stated their intention of focusing on reading skills for the co-planning target. As Amy said in the meeting, the team was inspired by the teachers of another project school who developed ‘a reading tip package’ to help under-achievers to complete reading comprehension tasks, and thus they would like to create their own reading tip package to support students. This instance suggested that the development of professional learning circle would be favorable to teacher empowerment.

School leadership’s support

The second type of support was from the School Principal. To enable collaboration among all teachers, the Principal reserved a common time slot in timetable for them to participate in lesson co-planning meetings. Upon hearing the team’s comment about insufficient discussion time at the end of the first project year, the Principal accepted the Subject Head’s suggestion of rescheduling the co-planning meetings and moving them to after-school hours in the second year. When asked to comment on teachers’ participation in the co-planning meetings, Mary and Elaine said in the interviews that they became more willing to raise questions and ask for clarifications due to the increased duration of the meetings. Moreover, the Principal granted the Subject Head power to rearrange lesson observations and post-observation debriefing sessions. Contrary to the previous practice of involving only teacher observees, the Subject Head and the Principal in the observations and the debriefing sessions, the Subject Head proposed opening both occasions to all team members because she believed this could promote reflection on how to implement DI strategies in their own classes. This change was perceived to be useful in promoting professional teacher development as Mabel said, “Other colleagues gave me sound advice in improving the activity’s implementation procedure” and Carol said “Mabel’s demonstration of the multi-sensory approach made me reconsider how to activate my students’ different senses with my prepared materials”. Inferring from these examples, we believed that the Principal’s support enabled collaborative lesson planning and reflections among all teachers.

Discussion

This study examines how teachers were empowered to develop their professional capacity to cater for learner diversity through implementing DI. Given the increasing diversity of students, the key question to many educators is how to cater for such diversity so that each student in the classroom can be well supported in their learning process. While the framework of DI and the associated strategies (Tomlinson, 2014) have been proposed for some time, there is limited empirical evidence showing how teachers could be equipped with the pertinent knowledge, confidence and capabilities in practising DI, especially in contexts where the student–teacher ratio is high and student diversity is huge, like the publicly funded school in our study (Brighton et al., 2005; Wan, 2017). Through a 2 year longitudinal study in this school, we showed how both experienced and novice teachers could be supported to develop heightened awareness of students’ diverse needs, professional knowledge of DI strategies, as well as experience of planning, implementing and reflection on lessons incorporating DI strategies. The iterative cycles of co-planning (with or without the curriculum consultant’s input), implementation and debriefing seemed to have facilitated teacher professional development. In particular, we would argue for the importance of the school-based nature of professional development in DI, since school contexts, teachers and students are diverse in many different aspects. Professional development workshops may motivate teachers to implement DI, but to help teachers understand how to accommodate students’ needs in their own contexts, school-based support (in the form of needs analysis, hands-on lesson planning and material design, lesson studies and reflection) seems to be indispensable (Opfer & Pedder, 2011). In this study, the consultant skilfully adjusted the intensiveness of her support so that she shifted more responsibilities and autonomy to the teachers. The duration of the professional development project (i.e., 2 years) may also play an important role, in the sense that the group of teachers could follow the same group of students, develop deeper understanding of their learning needs and accumulate more experience of supporting them with different DI strategies (Guskey, 2002). This element of continuity is favorable to professional development, particularly promoting “growth network” (Clarke & Hollingsworth, 2002), where teachers experience more lasting changes in their knowledge, beliefs and practice. Taking all these together, this study provides some empirical evidence on how teacher educators and school leaders could support teachers’ professional development in relation to DI, which addresses consistent calls for more research on the issue of enhancing teachers’ capacity to implement DI (Suprayogi et al., 2017).

This study has also conceptualised a three-stage journey of teacher professional development. This journey is similar to the one reported by Fang et al. (2004). When the professional development programme first started, the teachers involved were playing a more passive role, mainly receiving the input and support provided by the consultant through workshops and co-planning meetings. This stage is deemed inevitable, as it takes time for teachers to revisit their existing beliefs and perceptions, and to apply new knowledge in their situated school and classroom contexts. With more knowledge, experience and experimentation, the teachers started to play a more active role in proposing, implementing and evaluating new practices. The consultant also shifted more responsibility to them and duly appreciated and recognised their efforts. Such an active participation in the process and continuous professional support may have contributed to the growth in the teachers’ autonomy and self-efficacy, as reflected in their leading role towards the final stage of the project.

From the journey, we could identify the interplay of the six dimensions of teacher empowerment (Short, 1992). With the leadership’s support and recognition of the teachers’ contribution to the professional development project, the teachers were willing to participate actively in the process. For example, they could make decisions in curriculum design and material revision. With more participation, reflection and consultant’s feedback, teachers received more professional respect and experienced a growth in autonomy and self-efficacy. Our study also shows the importance of teachers working in a professional learning community with shared goals of helping students to learn, so that they could share the responsibility and exchange professional views. These findings largely echo Sancar et al.’s (2021) framework, where the relationship between teacher professional development and classroom practices is mediated by teachers’ characteristics (e.g., professional experience, competence, beliefs, confidence, knowledge), school context, coaching and collaboration within learning communities. In particular, our study further unpacks “teachers’ characteristics”, with reference to the notion of teacher empowerment and its various dimensions.

Our study thus corroborates the reciprocal relationship between teacher empowerment and teacher professional development (Gonçalves et al., 2020; Tannehill & MacPhail, 2017). When following this group of teachers for 2 years, we observed that professional development, in different forms, promotes teacher empowerment, which in turn reinforces professional development. Perhaps the relationship could be depicted more clearly in this way—teachers are empowered through their participation in professional development programmes or activities, probably due to their growth in professional knowledge and experience. The empowered teachers would then be more confident and autonomous in experimenting with new ideas, sharing with each other, and engaging in iterative practice-reflection cycles. Such cycles will then facilitate their professional development process. In this way, our study contributes to a more in-depth understanding of the process and interplay between teacher professional development and empowerment. Such an interplay plays a key role in sustaining teachers’ long-term, continuous professional development. This is because the professional support provided by any professional development programmes will eventually be withdrawn. It is through teacher empowerment that the impact of professional development programmes could be sustained and even extended to other teachers in the school and professional community. The focus of the professional development in this study was teachers’ capacity in DI, but we would argue that such a teacher professional development and empowerment journey would be applicable to other aspects or initiatives.

Conclusions

Drawing on rich qualitative data from multiple sources, this longitudinal case study unpacks the process of teacher empowerment through engagement in DI-related professional development. The findings suggest a three-stage journey towards teacher empowerment mediated by both external and internal factors. The findings also highlight the potential interplay of teacher empowerment, teacher professional development and its sustainability, which may cast light on constructing a sustainable model for teacher professional development. However, the conclusions drawn from this study may be tempered by two limitations. First, since this study was conducted in one primary school in Hong Kong, caution needs to be exercised when considering the applicability of the findings to other sociocultural settings. Further research is therefore warranted to verify the findings in different contexts, particularly the three-stage journey. Second, although the study has revealed the factors that may mediate teacher empowerment, it is questionable whether and how such factors may interact with one another. One promising avenue for future research is thus to investigate the potential interplay of those factors which could advance our understanding of how to create favorable conditions for teacher empowerment.