This work observes the social relationships among five and six year-old children with their toys and games based on an ethnographic fieldwork conducted in a Child Development Space in Rio de Janeiro city. Thus, it investigates how they understand, contribute to, and construct their notions of masculinity and femininity based on the perception that children construct themselves alongside their things. Drawing on Butler s contributions (2019; 2003) that through highly regulated practices, sex is materialized, reiterated, and reinforced, possibilities are opened to transcend such regulatory norms. Children, in turn, being social actors who relate to all these dimensions of society, also appropriate and perform gender, offering alternative ways of being and existing in the world. Building on Miller s (2013) and Mizrahi s (2007) elaborations that to make possible the constitution of our own selves we need to make use of artifacts and material objects, and that the use of artifacts allows gender to be performative, the aim is to demonstrate how children conceive what it means to be a boy and what it means to be a girl, considering that children s relationships with their toys assist in the formation of their gender notions. From this perspective, the work elaborates on gender with and from the perspective of children and their relationships with each other and with their objects.