Singer Melba Moore guest stars as Rudy's schoolteacher Mrs. Abbott. When her parents get a letter from her teacher, Rudy (Keshia Knight Pulliam) fears the worst. Actually, Mrs. Abbott is quite pleased with Rudy's classroom performance, except for the fact that the girl refuses to play the violin in music class. Accordingly, Cliff (Bill Cosby) invites classmates Kenny (Deon Richmond) and Kim (Naoka Nakagawa) to the house to rehearse with Rudy, despite Kenny's fears that the girls will clash--as in "clash of cymbals!" ~ Hal Erickson, Rovi