The kids in Ms. Frizzle's class are getting ready for the Wild Weather Show. To prepare, they take a field trip to the Weatherama Amusement Park. The class finds out just how wild weather can be when they accidentally fly right into a powerful tornado.

When Keesha discovers mold on her sandwich, Mrs. Frizzle takes the class on a tour of the mini microbe world where the kids learn first hand that these tiny beings can have huge effects.

Ms. Frizzle's class challenges Mr. O'Neatly's class to a science contest withamazing--and magnetic--results.