The dynamic of implementation of adapted Lesson Studies in France

International audience ; The implementation research reported here studies the dynamic of the implementation of adapted Lesson Studies (LSa) in France, a process initiated in 2016-2017 at the IREM of Rouen. Drawing in particular on the systemic and ecological approach offered by the anthropological theory of the didactic, we show how a hybrid object combining the LS and the IREM cultures of teacher professional development has emerged and consolidated. We identify an original, essentially bottom-up dynamic that exploits curricular and institutional changes, and mobilises an increasing diversity of contexts and actors. We question its potential and its limitations, in the light of the current state of implementation research, and reflect on the most appropriate models for it.