The kids are in the Bailey City Cemetery collecting leaves when they see a very tall, very skinny man carrying a huge black box. The man goes into the school building. They find he is their new band teacher, Mr. Belgrave. The band room is the old science room, otherwise known as the storage room. A skeleton nicknamed Claude is in the room. Liza thinks the skeleton taps his foot. Later, Eddie thinks the skeleton taps him on the shoulder. The kids keep hearing tuba music, but no one in the school can play it - not even Mr. Belgrave. They go into the school after hours and hear the skeleton playing the tuba. Mr. Davis, the principal, finds the kids in the school and scoots them out the door. At the Fall Festival Claude is on the stage and he is holding the tuba. As the kids perform they hear tuba music. When they turn around they find out who has been playing the tuba all along!