Cast of Back to School

Rodney Dangerfield portrays Thornton Melon, a successful businessman who decides to go back to college to help his struggling son and ends up having various misadventures.

Sally Kellerman plays Diane, Thornton's love interest and a respected professor at the college.

Burt Young takes on the role of Lou, Thornton's loyal and sometimes unconventional bodyguard and friend.

Keith Gordon portrays Jason Melon, Thornton's son who is initially embarrassed by his father's antics but eventually learns to appreciate him.

Robert Downey Jr. plays Derek, Jason's wacky roommate who gets involved in Thornton's schemes.

William Zabka portrays Chas, a competitive student who clashes with Thornton and Jason.

Paxton Whitehead takes on the role of Phillip Barbay, a pompous and conniving business professor at the college.

Adrienne Barbeau plays Vanessa, a companion of Thornton who adds some fun to his college experience.

M. Emmet Walsh portrays Coach Turnbull, the demanding and determined diving coach at the college.

Terry Farrell plays Valerie, Jason's love interest who supports him through his journey at college.

Ned Beatty makes an appearance as Dean Martin, the reasonable and fair-minded dean of the college.

Severn Darden portrays Dr. Barazini, an eccentric and intellectual professor at the college.