Kristy in Charge — Ann M. Martin

For one crazy week, the kids at Stoneybrook Middle School have become...teachers! Mallory faces an out-of-control English class. Mary Anne is student-teaching social studies. And Kristy has her first-choice assignment -- teaching gym!

There's only one big problem -- and his name is Cary Retlin. Cary and Kristy are supposed to be teaching the gym class together. But instead, they've started a gym war. Stoneybrook Middle School has never seen a teacher feud like this before -- and Kristy's determined to do anything she can to win.

The best friends you'll ever have!