When eighth grade begins, Cass Levin feels like the entire school is out to get her. She's stuck in classes without her closest friends Penelope and Tillie to keep her company. And as if that weren't bad enough, this is the year that students take an extended field trip to Elston Prep's nature retreat in the countryside. Cass confronts her problems with spirited resilience, and she forges an unexpected friendship with Rod Punkin, the school's biggest behavior problem. When Rod goes missing, Cass embarks on a secret rescue mission in this funny, witty, and utterly moving story about being thirteen.