Agenda de l'ENS de Lyon

There have been long-standing learning challenges in visualization in 3D geometry. 3D dynamic geometry environments (3D DGEs) offer teachers new opportunities for supporting student visualization but also raise issues, such as the tension between students’ perception and theoretic-deductive reasoning. This study investigates an essential teacher practice in 3D DGE integrated learning environments: the coordination behavior which supports students’ coordination of their own perception and different modes of logical reasoning. We further investigate how can this behavior be linked with the characteristics of the (dynamic) geometrical situation and teachers’ knowledge and views.
We establish a compound framework to address these questions. The Documentational Approach to Didactics (Trouche et al., 2020) serves as a global framework to integrate the regularities in teachers’ coordination behavior and the underpinning knowledge and views into a coherent unity – coordination scheme. The rules of coordination in the coordination scheme are further structured with the help of Toulmin's (2003) diagram of argument; the operational invariants in the coordination scheme are categorized with a framework built on Koehler & Mishra's TPACK (2009); the characteristics of the (dynamic) geometrical situation are also structured from several dimensions about the work of Piaget et al. (1973) and Morgan et al. (2009). Adopting a case study methodology and being situated in a Sino-French cooperation project, we use the compound framework to analyze the 3D DGE integrated lessons of experienced teachers in both France and China. The study finally leads to a renewed framework that allows capturing essential features of teachers’ coordination schemes, and opens new perspectives both for teacher education and for further research.