Elliott and I made these little leaf impression "coins" out of Sculpey clay and then baked them. He had the best time making the impressions with a glass, between wax paper. In the original instructions, you're supposed to write the name of the leaf on the back to help your child with leaf identification. Elliott and I just like holding them and looking at them. . . :)

Instructions at:
http://familyfun.go.com/crafts/home-garden-projects/gardening-nature-crafts/garden-crafts/leaf-tokens-876186/