The article presents selected results from an ethnographic study on the (re)production of gender in the classroom. In this analysis, gender is conceived as a principle manifested in interactions, a principle that structures the lives of individuals and the collective, and not as a complex of essential characteristics of an individual. Gender is analysed in relation to other categories like age and ethnicity. These represent additional re/constructed categories that influence social inequality. These categories tend to be viewed as natural sources of social difference and the legitimisation of inequalities. An analysis of the ways in which these categories are activated in the social field makes it possible to go beyond the boundaries of research on the reification of these categories. In this article, the authoress shows how these categories intertwine and connect and how the interplay between them is manifested in the behaviour and strategies of various actors, i.e. students, in the classroom.