In the future, corporations have taken over the world and banned sex. A group of rebellious high school students devise a way to go back in time to the present day and try change history to prevent that from happening.
At a sizable public college, high-minded student Eddy is forced to room with the slovenly Stuart, but the pair strike up a surprising friendship. When attractive co-ed Alex is assigned to live with the two male students because of her gender-neutral name, a roundabout love triangle ensues. Eddy secretly yearns for Stuart, who wants Alex, but she prefers Eddy. The complex situation leads to sexual experimentation and strained relationships.
The nerds are now in control of the university, as a result of Lewis Skolnick and the rest's actions in the two previous movies. A new generation of sportsmen arrive, however, determined on winning the school back. The principle, himself an ex-nerd fighter, helps them, and the nerds return to suppression. Harold Skolnick needs help from his uncle Lewis, the hero of the first two movies. Lewis, however, are not too proud of his nerd past, and won't reveal any of it, much less help his nephew. However, his wife makes him change his mind, and with help from his friends from the first two movies, they start the fight to win the school back, using classic nerd tricks.