When Harry finds an ad for a used telescope, Miss Mackle suggests that the class try to earn the money to buy it. They're studying the moon in school, and having a telescope would be just perfect. So the class gets together and decides to have a bake sale. As soon as they make enough money to get the telescope they plan to have a moonwatch and invite all the parents. Everyone is so excited - but no one knows that Harry has a surprise plan of his OWN for the big night.