The Recess Gang consists of TJ Detweiler, Spinelli, Gretchen Grundler, Mikey Blumberg, and Vince LaSalle. Together, they hatch a plan to infiltrate the school and stop Benedict. Along the way, they meet up with a group of kids who call themselves the "Ashley's," a clique of popular girls who initially brush them off but eventually join forces with the gang.
As they investigate Benedict's plan, the Recess Gang discovers that he's teamed up with an alien race called the "Follicles," who are using the Tractor Beam to suck up all the water from the Earth, in an attempt to make it more habitable for their kind. The group bands together, along with the help of a reformed Benedict and his army of ninjas, to stop the aliens and save Summer Vacation.
In the end, the Recess Gang triumphs, and Summer Vacation is saved. Benedict becomes the new principal of Third Street Elementary, and the Ashley's are accepted into the gang as honorary members. The movie ends with the gang enjoying their well-deserved Summer break.