This article discusses the results of a research based on a formative process involving basic school teachers and addressing the teaching of algebra through patterns and regularities. Using professional learning tasks specially designed for a formative process, the aim is to investigate the mathematical and didactical knowledge mobilized and deepened by mathematics teachers when preparing, developing, and collectively analyzing a lesson on patterns and regularities with high school pupils. This is a qualitative-interpretative research, in which data were collected through protocols and audio and video recordings. The results show that the participating teachers mobilized and expanded their knowledge with regard to the interpretation of different ways of generalizing a mathematical pattern, as well as expanded their mathematical knowledge about an important topic to discuss at basic school.
Algebra Teaching; Teacher Education; Professional Learning Task; Mathematical Knowledge; Didactical Knowledge