Sure, you've let your children blow off steam running through the outside spray fountains. And I know you've explored the interactive exhibits about bugs. But did you know you also can barter some of those curious seedpods and snakeskins you found on your last hike? Kidspace Museum's Nature Exchange allows you to trade your wild discoveries for other natural treasures such as polished minerals, shells and fossils. You are allowed to bring in three items at a time, and points are given based on both the item's rarity and your child's ability to explain it. The more research you've done together — they even have field guides there to help you look up all your finds — the better. By the way, ask me the history of ginkgo trees. 480 N. Arroyo Blvd., Pasadena. (626) 449-9144, kidspacemuseum.org.