Students develop a leaf classification system in this promising practice lesson. The lesson begins with a discussion of how classification systems are used in daily life. Students then work in small groups to design a classification system that correctly identifies each of the leaves in the set. Students then exchange classification systems to see if they can correctly identify leaves using another groups system.

This lesson would be a very good culminating activity for classifying plants by their characteristics in grades 3-5. It would be an appropriate introductory activity for studying biological diversity in grades 6-8. ORC content resource #417, What Tree Is It?, could be used along with this lesson as an example of a dichotomous key or to identify trees by their leaves. (author/ts)