Things to do in Oklahoma City

My parents are visiting from the UK, so we've been going out and about doing those 'touristy' things that you never do unless you have visitors, or are a visitor yourself in some other place. So far we've visited the National Memorial and Museum, commemorating the 1995 Oklahoma City bombing (very powerful and moving), the State Capitol (seriously impressive, especially the debating chambers) and the Oklahoma Railway Museum, where you can have a short ride on a genuine American train, which I got the impression was a first time experience for many of the adults taking part, never mind the children.

Remaining on our list of possible places to visit are the Oklahoma History Center, the Oklahoma City Zoo and Botanical Garden, the National Cowboy and Western Heritage Museum, Science Museum Oklahoma, and the Oklahoma City Museum of Art. I am still trying to persuade my parents to try the Oklahoma Museum of Telephone History and the World of Wings Pigeon Museum, but sadly they don't seem so interested in those...