Fifteen places every kid should see...what's on your list?

I would add to the list: Mesa Verde National Park, CO which for me is one of the most amazing. It is history of different people, culture, and great effort.
Two years ago we drove cross country from CA to MA with a 2 years old for a whole month. He enjoyed the trip, and wants to hear stories and see the pictures and videos all the time. It is the way for him to remember the trip.

I'd add the Kennedy Space Center it's really fun and they can learn alot about space and all the history that comes w/ it. And they get to explore inside and experience and discover amazing facts about space. They also provide some hand-on experience.

I would als add Wonderworks. That place is really fun and you get to see and experience things you may never had seen before. The building itself was built upside down and it awesome to see. There are many true, fun, and weird facts that they can learn about. You'll learn alot of shocking facts as well.

I love Washington DC...we go there every year and my boys don;t get tired of visiting those museums every year. On my list though is also Mount Rushmore. Also, if you guys ever come to Michigan, I would highly recommend Sleeping bear sand dunes. Check out this web page
www.nps.gov/slbe

All of Washington DC is a great idea--the monuments to the presidents, the war memorials, and Arlington and the tomb of the unknown soldier. So much of it is free to visit, and there's public transportation everywhere. Just make sure you give it enough time to see it. And be aware it's a HUGE place, so plan to be there a few days.

My other suggestion would be Niagara Falls NY and Lockport, NY. Niagara Falls just defies description and the locks in Lockport go hand in hand with 20th century marvels in attempting to get boats up and down the river to and from the falls. There is nothing like the sound as the locks shut and the water pours in to bring the boats up to the correct level. Not too many of us are going to get to Panama to visit the Panama canal, and this gives you an idea of what that would be like. And again, as a state park, Niagara Falls isn't very pricey (so much of it is free) and you can take a few days to cover the entire area.