A developmental evaluation approach to lesson study: exploring the impact of lesson study in London schools

This article 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. List of Abbreviations: HE: Higher Education; LS: Lesson Study; PD: Professional Development.