Kate and her friends embark on an after school adventure, in school. To surprise her ailing grandmother, Kate stages a plan and recruits the help of her friends. To their surprise, a few unwelcome classmates interrupt what could have been a simple task. Kate, a straight "A" student, shocks everyone by getting detention to start her elaborate scheme. Hunger hits, snake enclosures break, toilet mishaps occur, and they try to avoid the janitor, who makes this anything but easy. Unbeknownst to him, he holds the key to the whole operation. The kids must find a way to work together to avoid permanent detention.