Meet misfit Sophie, too used to bullies at Grey Stone Day School. Her classmates Julia and Molly tease her to no end and her teacher Mrs. Cook ignores the bullying.

The playground at Grey Stone has a special secret though: it's shared with the students of a monster school!

Craving acceptance and diversity, and trying to defeat her feelings of fear towards these strange and colorful monsters, Sophie bravely steps into the unknown and meets a little monster at recess—and makes her first friend. Through her friendship with the monster, she develops stronger feelings of self-confidence and self-esteem. In addition, she learns to stand tall and to appreciate differences and she discovers that sometimes you really can turn lemons into lemonade.