Speak, by Laurie Anderson

Melanie is an outcast at her high school. It wasn't always this way, but after she called the police at a party, she was rejected by everyone. There is no way she will let anyone know the truth about what happened during the party, and because of that, everything had gone downhill. Her grades went from straight A's to straight D's and she lost all of her friends. No one can get her to talk about it until her Art teacher assigns her a project, where she finds her ability to speak out, and tell the truth to everyone she knows.