List of things to do:
DC (I lived in MD, VA, & DC for about 9 years):
1. Air Space Museum Imax showing are excellent and nice way to relax.
2. Take pictures by the Washington Monument, White House, and Capital Building (Take the Capital Building tour if you have time.)
3. Lincoln Memorial (There is no greater iconic memorial personally on USA soil without him, we would not be America.)
4. If you have time. Go to Arlington Cemetery, Vietnam Memorial, Jefferson Memorial.
Florida (Travelled there several times):
1. Orland? If you’re in Orlando do the usual tourist stuff and check of the Lego store. I hear it's the largest according to square footage but it looked to have about the same content for sale as most stores to me
, just more of it.
California (Went there twice love both times, I'm assuming you'll be in SoCal?):
1. Obvious is Legoland.
2. Yosemite if you have the time. And Redwood National Park but you'll need an extra three to four days to drive up and back unless you doing a big loop around the country by car, or have plenty of money for flights. Same about south eastern loop out to the Grand Canyon.
3. Drive over to Las Vegas and stay one night. Lock all you credit cards in a locker in SoCal. Take $500-2000 cash and have good time. Fill up you tank with gas when you arrive so you have an easy exit plan.
Finally NYC (Never lived there, travelled there often):
1. Get a metro pass and use the crap out of it. Time Sq. & Ground zero are both a must.
2. Check out the Empire State Building for kicks and wiggles even though it's tiny. It's iconic NYC. There's a nice Korean restaurant on the same block that is excellent for lunch.
3. Go see the Statue of Liberty, thanks France she's pretty.
4. Go to the night club district if you're old enough and enjoy it. Nothing like NYC night life, don’t get me wrong: London, Ibiza, Miami, Vegas, DC, LA, Tokyo, Rio all have very lovely lovely lovely night life but NYC is NYC, it has its own flavor and style that is unique and well worth the libations. Nothing like several inches of snow, camels, and giant disco balls.
PS: If you want to see the "Real America" go to Lincoln, NE and watch a Cornhuskers game.