My dd13 is reading a series by Gerald Johnson – The Presidency, The Congress, The Supreme Court, and The Cabinet. So far, so good. There is a decent website called Ben’s Guide to Government or something similar, too.
Re. Visiting dc, contact your congressman well in advance to get tickets to tour the dome of the capital. This was a highlight of our trip! Everyone has to be able to walk hundreds of steps up and down though. We did get permission to carry ds1.5 at time in ergo carrier on hubby’s back. Also, not one of the free museum’s but we loved the Newseum. More later as I remember.