Invite students in grades 4-8 to study animal tracks and other clues at this website to learn about biodiversity. For example, in the Critter Catalog, students explore different classifications of creatures, including mammals, birds, fish, insects, and reptiles. In the Tracks and Sign Guide, students examine illustrations of animal artifacts–e.g., bite marks, pawprints, nests, egg cases, and other interesting finds–to determine what animal left that particular imprint behind. In addition, the site includes an Invertebrate Identification Guide featuring organisms commonly found in many schoolyards. The resource was created to highlight invertebrates common to the Michigan area, but many of the invertebrates are found in other locations as well.