Amazon.com description: Product Description: What do sponges, worms, and mollusks have in common? They re all simple animals. They are also unique, cool, slimy, fun, and (sometimes) creepy! There are hundreds of thousands of different species within these three groups of animals. From the color-changing cuttlefish to foot-long parasitic worms that infect humans and grow underneath their skin, from the colorful underwater sponge to the banana slug, sponges, worms, and mollusks are fun to learn about. In this book, you ll explore these diverse groups of animals through hands-on activities, projects, and experiments. Whether you try the projects for fun or for a science fair, you ll get an up-close and personal view of leeches, earthworms, snails, and more.