Investigating pedagogical content knowledge of teachers faced with a new curriculum on the evolution of chemical systems

Résumé En

A curriculum on the evolution of chemical systems was recently implemented in the final year of Higher Secondary Education in France. An epistemological analysis of the content of the curriculum and an analysis of the effects of teaching on students' conceptual development were made, in order to investigate the PCK teachers have developed when teaching this curriculum. In this communication we focus on the students' learning difficulties and errors teachers recognize or do not. We carried out semi-structured interviews including the presentation of authentic students' responses. Teachers are aware of several students' learning difficulties or errors they make, but they are not numerous to stress the difficulties students may have to revise their conceptions on chemical change to understand the chemical equilibrium concept. The presentation of students' responses (a) helps a teacher to develop his PCK in finding out that some students make errors that he was not aware of (b) reveals that some teachers have difficulties themselves. These difficulties concern more particularly the understanding of subjects involved in the models introduced by this curriculum.