Three O'Clock High (1987)

The nerd Jerry Mitchell is responsible for the student store at the Weaver High-School. When the troublemaker delinquent Buddy Revell is transferred from a continuation high-school, one teacher assigns Jerry to write an article about the notorious Buddy Revell to the school newspaper. Jerry stumbles upon Buddy in the bathroom and touches the shoulder of the bad boy that schedules a fight with Jerry at three o'clock at the parking lot. Along the day, Jerry tries to find a means to avoid the fight.