When Arthur's third-grade class goes hunting for fossils at Rainbow Rock State Park, his friend Buster actually finds one, and instead of turning it in Buster decides to take it home--but he soon regrets his decision.
Arthur is unhappy about going on vacation with his family, but he shows them how to make the best of a bad situation when they end up stuck in a motel because of rain.
Arthur gets fired by his new piano teacher, Dr. Fugue, for neglecting to practice, and then must find a way to convince Dr. Fugue to give him a second chance.
Although Arthur and Francine aren't speaking to each other, they must find a way to set aside their differences when they are locked in the library after it closes.
Arthur worries that he won't be able to play little league baseball as well as all his friends and faces lots of teasing until someone discovers teamwork.
Arthur's experience babysitting for the terrible Tibble Twins is as challenging as he expected, but he finally gets control by telling them a spooky story.
When a parent group bans a series of scary books from the local public library, Arthur and his friends devise a plan to get their favorite books returned.