The US Space & Rocket Center in Huntsville, Alabama is a real shrine to the American Space Program and rocketry in general, whether it be scientific or military. The museum is sort of an offshoot of Redstone Arsenal, home to the United States Army's Missile Command.
Inside, the museum, there are exhibits which range from ballistic missiles to artifacts from the famous
Apollo missions including the actual Apollo 16 command module and a lunar rover. Aside from just artifacts, the museum also has lots of interactive activities like wind tunnels and simulators which let kids (and adults) learn about the basics of rocketry and space flight as well as have some fun while they're at it.