<P> At the championship dive meet, father and son patch things up and, with a little distraction, Derek fouls up the opposing team's dives, while Chas gives a lackluster effort, followed by a near - perfect performance from Jason . Chas fakes a cramp out of spite in an effort to make the team lose . This gives the coach an inspiration . He calls upon Thornton, who comes out of the grandstand to perform an "impossible" dive, the legendary "Triple Lindy," to win the meet . </P> <P> Thornton learns that he has passed all his classes with D's, except from Diane, who has given him an A . The movie closes with Thornton lecturing the graduating class that the real world is hard, so: "Move back in with your parents...let them worry about it!" and "Look out for Number One, but don't step in Number Two!" </P> <Ul> <Li> Rodney Dangerfield as Thornton Melon </Li> <Li> Sally Kellerman as Dr. Diane Turner </Li> <Li> Burt Young as Lou </Li> <Li> Keith Gordon as Jason Melon </Li> <Li> Robert Downey, Jr. as Derek Lutz </Li> <Li> Paxton Whitehead as Dr. Phillip Barbay </Li> <Li> Sam Kinison as Professor Terguson (a.k.a. Turgeson) </Li> <Li> Terry Farrell as Valerie Desmond </Li> <Li> M. Emmet Walsh as Coach Turnbull </Li> <Li> Adrienne Barbeau as Vanessa Melon </Li> <Li> William Zabka as Chas Osborne </Li> <Li> Ned Beatty as "Dean" David Martin </Li> <Li> Severn Darden as Dr. Borozini </Li> <Li> Robert Picardo as Giorgio </Li> <Li> Jason Hervey as Young Thornton </Li> <Li> Edie McClurg as Marge Sweetwater </Li> <Li> Kurt Vonnegut as Himself (cameo) </Li> </Ul> <Li> Rodney Dangerfield as Thornton Melon </Li>

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