In this activity, learners sort and count different colored plastic dinosaurs by various attributes including tail length, whether or not the dinosaurs have horns, etc. Learners discuss the basis of their sorting, describe individual dinosaurs as well as groups and count the whole as well as subsets of the whole. This identification, sorting and grouping based on different traits (physical attributes, diet, habitat) provides a strong foundation for the development of the concept of species. The lesson plan also explains that dinosaurs lived a long time ago, but because they are no longer alive today, they are said to be extinct. Reasons for their extinction and the concept of endangered species can be explored.