When I worked at the Boeing factory in Huntsville, Alabama on a government missile project I had many weekends to explore the south. One highlight was a visit to the Marshall Space Flight Center at the US Army Redstone Arsenal. One of the first things people see is the Space Shuttle sitting on a rocket booster.
You can see a tiny people underneath it in the photograph. It's quite awesome. The Redstone Arsenal has a huge historical collection of missiles that one can see here.
But I wished most of all I was under 18. Then I could have gone to Space Camp, here's pictures from the 2010 International Space Camp. There's lots to do and much to learn here. I spent a whole day touring the facility.