My husband, me and our 2 boys (16) are going to Williamsburg for about 8 days. We would like to go to D.C. for a day. The boys have never been there. We plan on seeing only the Air and Space Museum and the Naturaly History Museum as these run toward the boys' interests. My husband and I have been there a couple of times and realize that D.C. is not a place you can plan on seeing all of in even a couple of weeks so we are keeping it simple. We also want them to see Union Station.
My question is what would be the best way to get there from Williamsburg? We don't even want to attempt driving and parking in the city. I was looking at driving to Fredricksburg and taking the VRE in. Is there a better way?

If you want to see Union Station anyway, take Amtrak! Might take a bit longer than driving (it's about 150 miles each way) but less tiring for the driver.

It's none of my business, but I can't help wondering about the time allocation -- 7 days in W'burg, 1 for DC.

I don't think Amtrak will work for the full Wmbg to DC trip unless you are doing an overnight in DC. The earliest train to DC gets you into Union Station at 1:25 barring any delay and the latest trip shown on the Amtrak site getting back to Wmbg leaves DC at 2:30. That would give you at best one hour in DC for 7+ train hours. If you want to train part of the way, you could consider driving from Wmbg to Richmond and training from Richmond to DC.

I live in Virginia Beach and when we travel to DC, we take the same route that you would take (I64 to I95). We don't like driving and parking in the city, so we normally stay in a hotel out in the "burbs" and catch a metro into the city. We found their metro very efficient. Here is their website:

http://www.wmata.com/metrorail/systemmap.cfm

If you can go on a weekend, it is very doable to drive in and park. I have been able to park right behind the Air & Space museum on a Sun.

I've visited both cities by rail many - I think it's exit times. Taking rail would be a big waste of time, unless you make the DC trip an over-nighter.

Instead, rent a car, drive to the Springfield/Franconia station (off I-95 I think it's exit 163) and take the Metro from there. You'll have missed the worse of the DC traffic, being south of most of it, and of course the infamous "mixing bowl" Another choice would be to try to catch one of the stations served by VRE (commuter rail) and take that to DC - but I understand most stations have inadequate parking. For example, you could take VRE from Fredericksburg, terminating at Union Station. Enjoy.

AUGH - typed out a long reply, hit a wrong button, and the whole thing disappeard!!!! So - a quick summary ....

Williamsburg - you should enjoy your time there. We spent 6 days there this past July. Williamsburg, Jamestown, and Yorktown were all quite interesting. The water park was a highlight - but we didn't do Busch Gardens. Quick note - the racecar place that is advertised in the Wmsbrg brochures/booklets is not worth it. It is very expensive and my sons (13, 15) thought it was "lame."

DC - Add the International Spy Museum to your list. It is not free like the Smithsonian museums, but it is well worth the money and your boys are at the right age to really enjoy it.

Thanks for all of your suggestions! We leave this Sat. and come back next Sat. I think we will try the Spy Museum. The boys would love it.
Will let you know how it goes.