Planning our first big road trip, with our 4 small kids. From Buffalo, NY to Des Moine and Fort Dodge, IA. Return trip will be to Philly and then back up to NY. We have scheduled events in Ft Dodge, Des Moine and Philly, but would like to plan some inexpensive fun things to do along the routes to burn some kid energy. Not looking for monuments or "stop and see" type things. Looking more for relaxing, fun memory making or fun shopping.
I-80 and I-90 will be a big chunk of our trip. We don't want to expend too much travel time getting to these bonus stops. Any ideas for me?