My plans to work through math and foreign languages along with history didn't work out. BUT, we are finishing SOTW3 with a summer study of American Colonies and Revolutionary War. We listened to "This Country of Ours", "The Autobiography of Benjamin Franklin" (for the mommy), "Our Island Story" (pertenent USA chapters) from Librivox.org for free. We were able to see the Liberty Bell and Independence Hall. Then recently we visited the Freedom Trail in Boston.
Stand-by travel is never free or easy, but useful while home educating these little people over the summer!