We're definitely going to visit the Air and Space museum. (I've been to that one a couple of times, but my husband has never been in DC before). Have been debating which other of the Smithsonian museums to go to. I love the National History one. One I want to see is the Post Office one.

The tourist bus sounds like a great idea. Thank you.

Renting bikes to see the monuments might not be a bad idea at all. We can't take our bikes because we're driving my car and do not have a bike rack for it. We have a bike rack for our pick up. The car (Monte Carlo) gets better gas milage.

I indent on wearing my best pair of walking shoes the entire time we're there.

Thank you all for the ideas.