The Substitute on MTV is an ambush game show set in a classroom. Students are surprised and thrilled when would-be substitute teacher Jon Gabrus shows up and announces that he is the host of a game show and someone in the class could win $5,000. Students face off to answer academic questions they “Should Know,” as well as pop culture trivia they “Do Know.” Finalists participate in physical challenges, then must answer polling questions based on responses from their peers.