Book excerpt: The book, Animals Have Classes Too!: Mammals, introduces young readers to animal classifications by explaining how mammals are grouped. Through photos, text, and sidebars, this title explores the differences and similarities between several classes, families, genera, and species of mammals, and how animal classification works. Readers will discover what traits put mammals in a class of their own. The Animals Have Classes Too! series for grades 1–3 gives an introduction to animal classifications, from kingdom to species. Each 24-page book in the series details how and why animals are classified, including common traits and various habitats, giving examples at each level. Each measuring 7.5" x 10", the titles in this series offer young readers an opportunity to learn more about Earth's magnificent animals.