Fern dares Arthur and his friends to enter the poetry writing contest at the local library, but writing poems turns out to be harder than they thought.
Arthur's Grandma Thora, a marbles champion, trains him for the first-ever Elwood City Marbles Tournament, but does not tell him that she will compete against him.
Arthur really wants to enter a song in the Crunch Cereal Jingle Contest, but when he cannot come up with a good idea, he enters a song his sister wrote instead.