Although Arthur loses the Super Chimp Club contest, his pupil, sister Violet, wins the first grade reading competition and a prize for them both.

Arthur the chimp is a little worried about losing his loose tooth, until his sister and their babysitter show him the real meaning of bravery.

While hurrying to get on the school bus, Arthur and his friend unknowingly switch their lunchboxes; later Arthur finds out what surprise his sister had put into hers.