Ms. Frizzle's class is in a Show and Tell contest. Arnold brings in an old artifact to show. But since nobody knows what it is, there's nothing to tell! So the class makes guesses as to what the object is, and they go on a wild adventure to find out if their guesses are correct. Designed to be accessible for younger readers, books in this series are easier to read, and follow the plot of the popular PBS Magic School Bus television series, based on the original Magic School Bus books written by Joanna Cole and illustrated by Bruce Degen.