Synopsis for
"The Simpsons" Lard of the Dance (1998)

Homer and Bart decides to start a grease buisness but are pushed out of it by two burly guys. Meanwhile, Lisa has to show around a snooty, mature new girl, Alex Whitney. She impresses all of Lisa's friends and convinces Principle Skinner to change the "Apple Pick" to a formal school dance, which Lisa isn't very into. She tries to act all mature so that boys will ask her out but instead makes herself look silly and decides against it. On the night of the dance, Homer and Bart try to steal the school's supply of grease but the pipe bursts and all the grease empties into the cafeteria causing the kids to have a "grease-ball" fight, which Alex won't join saying that it's too immature and disgusting. The episode ends where Lisa throws a grease ball at Alex, telling her to act her age, causing Alex to join in.