If you're looking for comprehension questions, check this freebie out! It has 15 comprehension questions and one open-ended essay.
In addition to all sorts of other President-themed activities, we visited http://www.whitehouse.gov/about/presidents to learn about and write 3 facts about two presidents each. Two presidents x 22 students = 44 presidential fact pages! We also wrote about three things we'd like to accomplish if we were President or one thing we'd accomplish and three things we'd do to accomplish it. We decided that it would be a pretty tough job!
We also took the White House virtual tour.
I showed students pictures from my visits to the Washington area a few years ago.
Ford's Theater, where Lincoln was assassinated by John Wilkes Booth
(closed for repairs when I was there)
The House Where Lincoln Died
Tomb of the Unknown Soldier at Arlington National Cemetery
Eternal flame and graves of JFK and his widow, Jackie
Visit the White House National Park if you're in the Washington, DC area!