Now that I see you still have time to plan, I'll put in my 2 cents. The Washington Post has an online Visitor's Guide that is very useful, for both long-range and short-range planning. At the moment, it is at http://tinyurl.com/ywgpfc or http://www.washingtonpost.com/wp-srv...l_visitorguide. If those links don't work, start at www.washingtonpost.com, click on "city guide" in the navigation bar, and then click on "visitors guide" - they have a "3 days in DC" article among other things.

And as a native of Washington DC (NOT Maryland, NOT Virginia, NOT "the DC area" - a little bit of local snobbism!) I'd say skip the White House. The Capitol, Library of Congress, National Archive, and Supreme Court and the Lincoln and Jefferson Memorials are all much more interesting... the White House tour itself is pretty blah, the rooms merely fancy rooms where important things happened once when they looked different. As locals, we never went there for a school trip. When I finally stopped in as an adult, I was bored out of my mind.

I am not Christian, but I have to say that the National Cathedral is glorious, and has wonderful architectural details, including modern stain glass windows (one with a moon rock, two honoring the labor union movement, etc.), and a recently refurbished organ. 2 problems - it is out of the way, so you'd probably want to catch a cab from the Tinleytown Red Line stop, and the guide materials available on-site are not as detailed as I'd like. But while it's not a usual 2-days-in-DC stop, if you have local friends who have a car and suggest it, it's not a crazy idea.

Finally, if you have any interest in Franklin Delano Roosevelt and his era, the FDR Memorial (between the Jefferson and Lincoln Monuments) is quite lovely - mostly outdoors, so not for a rainy day.