On countless playgrounds each day, girls are at work crafting intricate social arrangements through language and embodied action. In this ground-breaking ethnography, the interactions of girls of diverse ethnicities and social classes show that rather than avoiding conflict, they actively seek it out, challenging the notion that girls are inherently supportive of each other. The Hidden Life of Girls documents the language practices and interactive rituals used not only to sanction friends who violate social norms, but also to bully younger girls and those regarded as social outcasts. This volume will not only provide a clearer picture of children's worlds, but will also help guide future policy and intervention strategies in schools.