Always a great experience to take the kids for a train ride to feed the bison. We live in Cheyenne, and whenever we have visitors to the area, we take them to Terry Bison for lunch and a train ride.
Though the old adage of "do not pet the fluffy cow" remains true even here, you are able to get so much closer to bison than in any other setting, and in a safe environment. It's a great opportunity to show kids (and see for yourselves) the majesty of the American bison.
Definitely recommend those coming through or staying in Cheyenne take a few hours to head down to the Terry Bison Ranch and check things out.