For the kids of Third Street School, there's only one thing better than recess, and that's summer vacation. It's been a long, hard year, and now T.J. Detweiler is ready to play hard - he's got nothing to do except hang out with his friends. T.J.'s plans go awry, however, when he finds out that all his pals are going away to summer camp without him - leaving him alone all summer. It doesn't take long for boredom to set in. He's so desperate for something to do, he even considers hanging out with the school snitch. His boredom comes to an end when, riding his bike past the empty schoolyard, T.J. notices an eerie green light emanating from the main building. Convinced that something weird is going on in the school, T.J. tries to tell his parents and the local cops, but the adults just dismiss his concerns as the overactive imagination of a bored kid. T.J. finally turns to the curmudgeonly Principal Prickly, who, with some cajoling, finally agrees to investigate; however, when the principal attempts to unlock the school gate, he is dematerialized in a storm of electricity. His worst fears realized, T.J. summons his friends - Spinelli, Mikey, Vince, Gretchen and Gus - back from their camps. At first skeptical of T.J.'s story, the gang become believers when they see a giant weapon emerge from the school's roof and fire a laser beam into the sky. Their school and principal in obvious danger, the gang decides to sneak into the school to investigate, but they are quickly discovered by the bad guys, led by an evil renegade ex-principal. In the chase that ensures, T.J. is captured. All seems lost, until the gang gathers together every kid they know, and with the help of their teachers, vow to take back their school.
