Ms. Frizzle decides to take the children to the local planetarium in order to learn about the solar system, though when she finds that the place is closed, she decides to turn the magic school bus into a rocket and the class heads out into outer space to learn as much as they can firsthand. However, a guest to the classroom named Janet is starting to lose her composure, as she doesn’t think it’s possible for them to have actually gone into outer space.