Another charming and funny adventure in the Mr. Wolf's Class series! Mr. Wolf's students are settling into their new classroom, and Randy, Aziza, and Margot realize they have some questions: What happened to Aziza's favorite Frisbee? Is the girls' bathroom really haunted? Where is Mr. Greens, the teacher who disappeared? The three friends want to discover the answers together, so they start a mystery club! Meanwhile, Abdi has his own questions about what happens to the balls that are accidentally kicked over the fence during recess, and thinks he'll be a hero if he can find his best friend's football. Mysteries abound at Hazelwood Elementary!