Whenever a friend comes in to town for a visit the first place I take them to is the National Aviation Museum. It's difficult to even describe how massive it is. There are dozens of planes hanging from the ceiling, a replica town from the 1940's, planes all over the place that you can actually get into and play around with and Nixon's old Air Force One chopper! There is also an IMAX theater, flight simulator and restaurant. The museum is based on donations so I love that families of all income levels can enjoy it.