I'm taking my family to DC in a couple of weeks and we are planning on hitting the Smithsonian, the Washington Monument (pre-ordered tickets on-line), and the National Zoo. I'm also hoping to hit Mount Vernon on the way home.
I won two rooms for Sat - Mon at the Marriott Metro Center (3.5* convention center) off of Priceline for $60 per room/night. It looks like a nice hotel, but parking is valet and costs $35/night. The best thing about this hotel is that the metrocenter is right there.
One thing I'm hoping to do is watch "Night at the Museum" at the Air and Space Center's IMAX theater. We also want to go to the butterfly arboretum (can't remember which museum that is in).
If anyone has any food recommendations in the downtown area (reasonably priced and nothing too fancy or exotic since my kids are picky), I would appreciate it.