After I added this book to my 2½ year old's bedtime book list, she finally understood why we wash our hands. I think having an image of germs (which look like tiny monsters in this book) helped her to understand what I had been talking about all along. When we both got a cold this month, I asked her why she thought we got sick, and she said it was because of germs, and we agreed that we should wash our hands more. Despite teaching us something, the book is fun to read, and I like the illustrations. Recommended.