This amazing state has so much to offer in the way of family vacations.  On a visit to the Badlands of South Dakota, the kids can count all of the different license plates in the parking lot of Mount Rushmore, which just celebrated its 60th anniversary.
You can explore caves, pick up rocks blasted from the mountain where the colossal statue of Chief Crazy Horse is a work in progress, join a "dig" at the Mammoth Site where more than 50 giant mammoths were trapped more than 26,000 years ago, and take a Jeep tour through a buffalo herd.
You can stay at Custer State Park, where besides seeing the buffalo, you can rent an old-fashioned cabin on a lake starting at under $150 a night, go gold-panning, or make animal tracks with the kids at hands-on junior naturalist programs.