In this article, the author describes a short activity which introduces third- to fifth-grade students to animal classification. The Tree of Animal Life activity is a simple, sorting exercise that can help them see a bigger picture. The activity sets the stage for learning about animal taxonomy and introduces the characteristics of various animal groups in a general way. Though the activity does not teach about each animal group's characteristics in great detail, the process of sorting of atypical examples (e.g., bat, octopus) does spark interesting discussions among students on the differences between animals and how scientists classify them. (Contains 2 figures and 1 resource.)