Have kids help you make homemade trail mix, also known among backpackers as gorp. Here's how to make a kiddie mix variety of gorp. You'll need 4 cups of Chex cereal, 1/2 cup of dried fruit bits (apple chips, banana chips, or dried cranberries), 1/2 cup raisins, 1/2 cup salted peanuts, and 1/2 cup M & Ms. Mix it in a large bowl or pour into a gallon-size re-sealable zipper bag and shake.
Read more about day hiking with children in my guidebook Hikes with Tykes.