Toy Soldiers (1991)

Billy Tepper is the leader of a group of rebellious boys at The Regis School. He has already been expelled from three prominent private schools. His best friend, Joey Trotta, is the son of the Head of the New York Mafia; Billy, all their friends and many other kids at the school have equally influential and prominent, if more law-abiding, parents. When Luis Cali's father is put in jail, he heads for the Regis School to put the son of the judge in charge of the case under hostage, only to find he has been removed. However, once he realises who the parents of the rest are, he decides the entire student body of the Regis School would be an even better bargaining chip.