Walnut Creek Regional Park in Urbandale has a playground, climbing tree play structures and a wooded area and creek to explore. It's a large park with multiple entrances, but
Google Maps should lead you to the playground area. There's no parking lot and no restroom, but it's fairly easy to park in the neighborhood.
You'll see the playground first, then head east down the trail to find the climbing trees and from there head east on the trail again to find a bridge, which has a great creek area for kids to explore.
