In this talk I present a framework to address participation in the mathematics classroom. This framework represents my journey through mathematics education research from a largely cognitive approach (with a focus on understanding and beliefs) to a sociocultural perspective (with a focus on context and valorization of knowledge). Some of the questions I discuss are: what does it mean to be good at math? Whose knowledge and experiences are represented? Whose and what approaches are valued? Which language(s) and forms of communication get privileged?