Fourteen-year-old Simone is having trouble making friends at her new school when her leadership studies class is paired with kindergarten students to mentor throughout the school year.

To her surprise, Simone enjoys the Kinderbuddy Project, and she develops a special friendship with her Kinderbuddy, Lily. But as the bond between Simone and her Kinderbuddy grows, she realizes that a crisis is looming in Lily's family. Simone calls upon Aaron, the reluctant heartthrob of the class, for help, and they become key witnesses to events neither of them could have predicted.