Purpose The purpose of this paper is to explore the popularity of Japanese lesson study (JLS) beyond Japan and the challenges this translation might pose. It notes that there is not a universally accepted definition of lesson study (LS) and seeks to identify the “critical components” of JLS through a review of the literature. It then uses a systematic literature review of recent studies of the implementation of LS with in-service teachers beyond Japan to analyse the models of LS used against these seven critical components in order to explore the degree of fidelity to the Japanese model. Design/methodology/approach A broad review of the literature on JLS available in the English language identifies seven “critical components”. A systematic literature review of 200 recent English language studies of the implementation of LS with in-service teachers beyond Japan is then carried out. Articles published between 2005 and 2015 are explored, including peer reviewed articles, scientific journals, book chapters and PhD dissertations. This systematic review enables an analysis of the models of LS used in studies from beyond Japan against the “seven critical components” of JLS. Findings The analysis shows that there is not an internationally shared understanding of Japanese lesson study (JLS) and that many of the missing components are those which distinguish LS as a research process, not simply a collaborative professional development approach. It also reveals that UK LS models seem particularly far from the Japanese model in those critical components which connect teachers’ knowledge and understanding within groups, to knowledge and understanding that exists beyond it. The study discusses whether these differences could be attributed to structural or cultural differences between Japan and other nations. Research limitations/implications The search for descriptions of the JLS is limited to articles available in the English language, which, therefore, represent a quite limited body of authority on the “critical components” of LS. The systematic review is similarly limited to English language articles, and there is a clear bias towards the USA, with the Far East and the UK making up the majority of the remaining studies. The study suggests that future research on LS beyond Japan should consider teachers’ attitudes towards the research elements of the process as well as their skills and confidence in carrying out research into practice. Practical implications The study strikes a note of caution for schools wishing to implement JLS as an approach to teacher professional development in the UK and beyond. Japan’s systemic approach has embedded LS experience and expertise into the education system, meaning a uniform approach to LS is much more likely. In addition, other systemic challenges may arise, for example, UK professional development time and resources is not designed with JLS in mind and may therefore require a significant reworking. Originality/value Whilst several systematic reviews of LS have explored its growth, geographical spread, impact and key features, this study provides a different perspective. It analyses whether and to what degree the “lesson study” models these studies describe align with the literature on JLS, and the implications of this for researchers and practitioners.

Purpose The purpose of this paper is to present the findings from a systematic literature review of recent studies of the implementation of Japanese lesson study beyond Japan, reviewing evidence of impact and robustness of the studies. Two studies of the implementation of lesson study from outside the timeframe for the literature review are also reviewed in detail, in order to explore the problematic nature of impact evaluation of lesson study. Design/methodology/approach A systematic literature review of 154 English language studies of the implementation of lesson study with in-service teachers beyond Japan published between 2006 and 2016 identifies 56 as a measuring impact. A lesson study-specific adaptation of Guskey’s (2000) five levels for the evaluation of professional development enables an analysis of the types of impact measured. An analysis using the Maryland Scientific Method Scale (MSMS) enables a review of robustness. Two recent robust studies from beyond this timeframe are then analysed in detail in terms of their framing of lesson study as an intervention and selection of related impact measures. Findings The literature review and subsequent analysis shows that studies are largely small-scale US case studies ranking as 1, or “least robust” on MSMS. Studies demonstrate the impact of lesson study on teacher learning and positive reactions, but little evidence of it making a difference to teaching, nor of the impact on schools’ professional learning cultures and structures, is present. The detailed analysis of the two recent studies shows that there are many potential pitfalls for researchers to avoid when measuring the impact of lesson study, specifically in relation to distinguishing lesson study as a professional development intervention, and measuring its impact accordingly. Research limitations/implications The systematic review is limited to articles available in the English language, and there is a clear bias towards the USA. The study suggests that future research on lesson study in the UK and beyond should evaluate the implementation of lesson study over a larger scale, gather evidence of the difference lesson study makes to daily teaching and learning, and to its effect on school culture and structures. Practical implications The study suggests that researchers should pay careful attention to the fact that lesson study is not an end in itself, merely a means to achieve an identified change to teaching and learning, and design impact measures accordingly. Originality/value Unlike other systematic reviews of lesson study, this study analyses the impact evidence for lesson study that might be seen as most relevant to its introduction in cultural and structural contexts beyond Japan. It also explores in detail the potential pitfalls of lesson study impact evaluations, offering guidance to both practitioners and researchers.

This paper presents a methodology for the developmental evaluation of a lesson study programme in primary and secondary schools. Our approach combined the principles of, i) user-focused evaluation, in which as evaluators we acted as participatory members of the innovation team and sought to involve users in the design and implementation of evaluation tools, ii) a multi-level logical model to guide data collection and impact measurement, and iii) an 'improving rather than proving' approach to evaluation. The evaluation tools were used on a programme to promote lesson study in London schools involving 133 teachers and 33 schools. The evaluation methodology included outcomes at school leadership, teacher and student levels. Issues of internal and external validity are discussed and strengths and weaknesses are described. Findings showed promise in the use of our scale to measure changes in teacher pedagogical outcomes and in the recording of qualitative changes to both teachers and students as a result of the lesson study cycles. Suggestions for the future use and development of this methodology are proposed, including better use of control groups and quantitative measures to record changes in learning outcomes for students.

Purpose Japanese lesson study (LS) is a professional development approach in which teachers collaboratively plan a lesson, observe it being taught and then discuss what they have learnt. LS’s global spread is increasing but studies have identified several challenges to its implementation: the lack of structures and systems to accommodate LS (especially time); the focus on demonstrating short-term impact; a lack of teacher research skills; a dearth of access to quality learning and research material; the absence of available koshis; and accountability pressures. The purpose of this paper is to examine the “translation” of Japanese LS through a case study of one English secondary school. Design/methodology/approach This study is a case study of a single school which has been using LS as an approach to professional development for five years. A documentary analysis of the school’s LS Handbook sought to understand the school’s approach to LS as articulated by senior leadership. Six observations of the schools LS processes were then carried out including planning, research lessons and post-lesson discussions. Finally, one senior leader who had led LS implementation and five teachers who had been working in the school during the implementation stage were interviewed. The findings are analysed against Seleznyov’s (2018) seven critical components of Japanese LS. Findings Several key deviations from Japanese LS are identified including: a lack of whole school theme studied over time; little kyozai kenkyu and no written lesson planning; teachers deviating from the role of observers in research lessons; no facilitator and little use of discussion protocols; no koshi; and struggles to ensure mobilisation of knowledge between LS groups. Several of these represent gaps between the school’s LS policy and practices. The findings show that LS practices have become diluted over time and that giving teachers choices seems to have led to teachers not adhering to important aspects of the LS policy. Research limitations/implications One of the limitations of the research is its focus on the perceptions of a small group of teachers who were likely to be more passionate about LS than others, and perhaps a deeper understanding of the challenges to implementation might be enabled by interviewing a wider range of engaged teachers, especially those who are perceived as “resisting” full engagement. Further research might also explore whether the implementation challenges faced by this school are replicated in other English schools and in other countries using LS as an approach to professional development. Practical implications Several implications for English school leaders seeking to implement LS are discussed, including the need to articulate the rationale for the protocols that shape LS, especially for staff new to the school and to check that important protocols are adhered to over time. Originality/value Whilst several studies of LS in the UK have explored its impact on teachers and pupils, and the challenges and successes of introducing LS into a UK context, this study provides a different perspective. It explores the challenges of using LS over time as a consistent approach to professional development in a school and seeks to understand how both resistance and dilution can affect its impact on practice.

Lesson study is increasingly prevalent as a collaborative activity in which teachers take part to explore their practice. There are many variations in how lesson study manifests itself, even in Japan, where it originated. However, in Japan, fundamental to lesson study is a focus on collaboration in researching teachers’ professional practice. In this article, we draw on experiences of our collaborative research with colleagues in Japan to provide theoretical insights into how we might conceptualize and inform future developments of lesson study as action research that informs curriculum design and implementation. The approach taken develops ideas of the theory of didactical situations, and draws on the construct of boundary objects to understand Japanese lesson study. We identify a class of artefacts, didactical devices , that may provide a useful form of boundary object that supports the collaborative action research of lesson study. Although the particular focus of the work presented here is mathematics, the lessons that we draw should have applicability across the curriculum more widely.