Based on an extraordinary array of diaries and letters, this work explores the shifting experiences of adolescent girls in the late 19th century. What emerges is a world on the cusp of change. By convention, middle-class girls stayed at home, where their reading exposed them to powerful images of self-sacrificing women. Yet in reality girls in their teens increasingly attended schools - especially newly-opened high schools, where they outnumbered boys. There they competed for grades and honour directly against male classmates. Before and after school they joined a public world beyond adult supervision, strolling city streets, flagging down male friends and visiting soda fountains. Poised between childhood and adulthood, no longer behaving with the reserve of "young ladies", adolescent females sparred with classmates and ventured new identities. In leaving school, female students left an institution that had treated them more equally than any other they would encounter in the course of their lives. Jane Hunter shows that they often went home in sadness and regret. But over the long term, their school experiences as "girls" foreshadowed both the turn-of-the-century emergence of the independent "New Woman" and the birth of adolescence itself.