The purpose of this article was to show the use of a design-based research approach to refine the use of Lesson Study methods to develop the teaching and learning of pupils identified as having moderate learning difficulties (MLD) in secondary schools. The findings suggest beneficial outcomes for pupils and teachers. The findings about pupil demonstrate of positive pupil learning outcomes in a particular context and use of Lesson Study. In addition, teacher level evaluation data found largely similar and very positive outcomes for the teachers concerned.