Hi there,
If adventure is what you guys are after,
Indiana State Parks, National Parks, etc. offer you hundreds of
camping grounds sites.
A good
recommendation would be KOA Campgrounds as it caters for small children. However, as you pointed out, your kids, consider then the Jellystone Park Camp-Resort and Amusement Resort where you camp out in cabins. They offer a whole range of
activities for kids like roller coasters, waterparks, and so on.
Hope this helps
VacationBuddy