Resumen

The aim of the current study is to discuss the mathematical knowledge changing process in future Math teachers. Based on the theoretical framework provided by the culturalhistorical approach of Psychology and, mainly, of the Activity Theory, the study highlights the mathematical knowledge of teachers from the movement that inserts them in the educational activity. The formative experiment was herein used asmethodological procedure. The experiment was set and developed with Mathematics pre-service teachers from a Brazilian public university, throughout a school year. The results indicate the need of organizing the teachers’ education process as a way to allow teachers to experience the teaching activity, as well as to reason about it and to becomeaware of their actions in order to overcome the humans’ alienation from themselves. Thus, we believe in the possibility of having a transformation process through the teaching activity in Math teachers. Therefore, it is possible to change their mathematical knowledge.