Simpsons Season 6, Episode 8: Lisa on Ice

Lisa discovers that she is failing gym class. In order to pass, she joins a local ice hockey team as their goalie. This creates an intense sibling rivalry between her and Bart, who is jealous of Lisa's abilities because he had always been the family's star hockey player. Marge tries to resolve their conflicts by reminding them that they are not in competition with each other, but this backfires as the next fixture is between Bart and Lisa's teams.