This thesis intends to understand the construction of gender in everyday interactions, practices and discourses carried out by young adolescents in secondary education, in a school context. The investigation is guided by the starting question: what are the processes by which young people in secondary education build gender identities, given the greater plurality of identity combinations that can be explored in the contemporary context in the Portuguese context. A research was carried out based on a qualitative methodology, using the observation technique and analysis of discursive production of focus groups and individual interviews in three public secondary schools in Lisbon involving students from the 10th to the 12th year of schooling.