Resumen

In the last decade, the Study and Research Group on the Education of Teachers who teach Math – GEPEFOPEM (Brazil) investigated teacher education groups constituted as Communities of Practice – CoPs. The objective of this paper is to discuss the focus of one of these CoPs when working with Proportional Reasoning and the practice elements of four CoPs, which promoted the development of their members’ professional identity. The data was collected through an analysis of meaning negotiation processes, mobilized knowledge and the CoPs dynamics based on different groups interactions and written production of their members. The analysis showed that self- knowledge, beliefs and concepts, professional knowledge, vulnerability, and the sense of agency became the focal points of the CoPs during the study of proportional reasoning as well as the practice elements of the four CoPs that promoted the professional identity development of, namely: shared repertoires, reports and discussions on their pedagogical practices, the existence of an open and flexible work plan, the opportunity to discuss their written productions, vulnerability experiences, the search for a sense of agency balance, connections among observations and empirical interpretations and a broader theoretical background, reports and discussions on previous meetings. Factors such as respect, trust, challenge, solidarity, projects negotiations, dynamics and actions, valorization of the singularities, and professional practices of teachers are essential for the constitution of the professional identity of these professionals and for the cultivation and maintenance of these groups.