The roboworld is really amazing. This place is geared for children and quite expensive, but things geared towards kids are usually really fun for adults too!
The sports center was really cool as well. I would recommend this place for kids + adults.
The submarine was also really cool to go on. You get to see the inner workings and they have the whole thing laid out. It is really neat.
We came during chemistry week so lots of tables with cool things.
I cannot wait until I go back to Pittsburgh and get to see the Musuem of Art.