This thesis studies the construction of the place of the child and the adolescent as subjects of rights from the Statute of the Child and the Adolescent. As an initial goal, it establishes a reading of children s rights as a complex process of changes and practices in the construction of a new culture. The ECA established institutional arrangements such as laws, programs and bodies that set up an institutional circuit generating new practices in everyday life. But, at the same time that it functions as an advanced juridical-institutional transformation, the ECA triggers an abrupt and untimely action in the daily life of Brazilian society. Actors were put in dialogue for the validation of this right, in this sense, a new perspective of rights brought with it the actor s valorization and his ability to act in a network within a new logic of public management. The real effects of ECA innovations can be seen in the light of the child s presence in the public space, usually where they are invisible, and where their right to the city tends to disappear. Through empirical research, the study will show trajectories of children and adolescents from the Favela de Rocinha, in Rio de Janeiro, with passage through the Guardianship Council, through plots and case reports. This study also includes, in a complementary way, an analysis of the relationship of this Council with some agencies that make up the Network for the Protection of Children and Adolescents - Public Prosecutor s Office, Social Assistance Reference Center and School - in order to understand how each one of these agencies, in its way of functioning, reveals the fragility to which children and adolescents of popular origin are exposed.