I HIGHLY recommend this!
My son Wess and I attended both the first event in the Fall of 2010 on the Mall in DC, and the second one at the convention center in the Spring of 2012. He met an astronaut, the Meteorite Men, saw space hardware (Dragon, Merlin, Orion), LASERS, 3D printers, robots, flexible solar panels, a storm chaser DOW truck, and much, much more....
This is a fun event for kids of all ages, especially school aged and interested in STEM. We won't be able to make it this year (only have three events scheduled that weekend so can only do one).
A few pictures from 2010:
|Meeting the Meteorite Men|
|SpaceX Dragon mock-up|
|Doppler on Wheels (DOW) truck|
Some of what we saw in 2012:
|SpaceX Merlin Rocket Engine|
|Really big ROBOT|
|Games and Activities (this was with IR)|
Wikipedia has a lot of additional information including the history of the event.
The festival will be in downtown Washington, DC in a couple of weeks:
Walter E. Washington Convention Center
April 26 & 27, 2014, 9am-6pm