It's Ms. Frizzle's birthday but, her students forgot to bake the cake. A field trip to a bakery seems like the perfect solution. When they get there they realize they don't have any of her favorite cake, chocolate. The kids accidentally get shrunk, make cake batter, and learn about chemistry in the process. Then the baker ends up baking the bus inside the cake.
The plot is very organized and is a simple way of teaching science to an younger audience. The book uses visual presentation and words to get the reader engaged in the learning experience. I see a lot of play on words that makes the subject of science more fun.I would use this to teach the strategy of using words to engage your reader in the subject.