Spent a great day at NASA, and even though it was a cold day with drizzling rain enjoyed the tram tour. Get in line early for the tram, and be prepared to wait 20 minutes ( in case you get cut off after the first 80-100 people board.)
Give yourself at least 4 hours to experience most attractions. Pass on any of the movies if you run out of time ( you can catch similar on You Tube).
It was great to enter the shuttle sitting on top of the 747, or sit in Mission Control to watch live updates of the International Space Station. There are tons of hands-on experiences for kids ( of all ages!) .
Take your own food/drinks ( coolers not allowed) if you wish to save on pricey concessions.
Well worth the entrance price, for a valuable, educational experience.