摘要:Our study intends to focus the teacher mediation of student learning in sciences' classrooms in new theoretical and empirical perspectives. The science teacher action, in a research perspective, has been considered as the sum of several aspects. Our research problem is how to consider, in a scientific way, the mediation of student learning in science classroom by facing the teaching activity as a whole. We present a theoretical framework to analyse the teacher mediation. We also developed an innovative methodological instrument to obtain data relevant to analyse the teacher mediation. Our instrument is a multimodal account of what happens inside the classroom or what particular context conditions some teacher decisions. We provide preliminary results from two particular science teachers to evidence the usefulness of this framework, in particular the dimensions of analyse and the richness of the instrument to collect data from multiple sources.