Stephen F. Udvar-Hazy Center, 14390 Air and Space Museum Pkwy; Chantilly; 703.572.4118
The kid in you is going to also enjoy the Air and Space Museum's Stephen F. Udvar-Hazy Center at Dulles, where you'll check out sweet flying machines, including a Lockheed SR-71 Blackbird, a Concorde, and the space shuttle Discovery.
Tidal Basin Paddle Boats, 1501 Maine Ave SW; Tidal Basin; 202.479.2426
Mom is probably going to want the kid to be all tuckered out by the end of the day, so let him or her paddle-boat their hearts out in the Tidal Basin, next to the Jefferson Memorial.
THE GUEST: YOUR GRANDPARENTS
While it's not always the most exciting geriatric pill to swallow, hanging with the old folks does have its rewards, and we're not solely referring to an inheritance. Show the still-happily-ever-after couple a great time with these quick hits, and take pictures, cause you know... Nevermind.
Hillwood Estate Museum & Gardens, 4155 Linnean Ave NW; Forest Hills; 202.686.5807
Take a leisurely stroll through the gardens of Hillwood Estate, and then head into the former home of Marjorie Merriweather Post, where Grandma will get super jeal while looking at all the Russian and French jewelry.