Earthworms are nature's best friends. By having his own worm farm, your child learns how earthworms irrigate the soil to help the growing process. Plus, he'll just like the look and feel of the worms.
To create your farm, find a large cardboard box with a lid. Add soil, kitchen scraps, and wet newspaper on the bottom. Place the box in a shady area and punch holes in the lid. Add your worms (dig them up or purchase them at your local nursery) and cover with a layer of wet newspaper and soil. Sprinkle with water and cover with the lid. Let your child feed the worms daily. Every few days have him take a few worms out to place around the yard or in his garden.
Sunflower in a Shoe
Kids love sunflowers, and your child will love having her own sunflower shoe. Find a pair of old, tall boots (look in your basement or at a garage sale) and fill them with soil. Your child can decorate the boots before you fill them with dirt if she'd like. Place two sunflower seeds in each boot. Place the boots in a sunny location; water daily and watch the flowers grow. Will they get taller than your child?
Let Nature Do the Talking
There are other outdoor activities you can do that don't have to do with growing. One evening sit with your child in your backyard and watch the stars and the moon. Listen to the crickets. Watch the lightning bugs. You'll learn a lot about nature and a lot about each other, too!