Pedagogical content knowledge about the sustainability of high school chemistry and biology teachers

Pedagogical content knowledge is specialised knowledge resulting from the practice and experience of the teacher in the classroom. This research aims to analyse teachers’ thinking based on the study of this knowledge and its application to sustainability in teachers who teach the subjects of chemistry and biology at the high school level in Mexico City. The methodology was a multiple case study of ten in-service high school chemistry and biology teachers. The results made it possible to analyse the teachers’ thinking about teaching sustainability in the context of biology and chemistry about the following central topics: ecological balance, natural resources, biodiversity, ecosystems, environment, energy, climate change, and pollution. It was possible to obtain information about how teachers understand teaching–learning processes for sustainability, their knowledge about the topics analysed, the strategies used, the representations and the different evaluation activities they use, and the difficulties that arise when teaching sustainability in their classes.