Gimme a Break! (1981)

S1E11 Katie the Cheat

The chief has high hopes for Katie's performance on her final exam, but she persuades Julie to take the test in her place. When the family learns about this deception, they are stunned, especially when Katie refuses the money they offer her for college, admitting to cheating. The chief is furious but soon discovers that it was actually Julie who sat for the exam. Realizing her mistake, Katie sincerely apologizes and resolves to retake the test by herself.