We traveled full-time with our last teen. This was in 2000, so I'm sure there are more computer courses out there now, even if you have to buy a disc. We used the Math curriculum we had been using for several years, so really no change there. His dad (at different locations for work much of the trip) and I are both good at math, so we just had a book for each year. We tried to focus on connecting our studies to the areas we were traveling. Visitors' centers and local people are great to answer, "What would be on your "do not miss" list if you were trying to learn about the history and economics of this area? Our son was into the Civil War in a big way, so we visited lots of sites, from the starting battle, to the site of the ending. Oak Ridge, TN was amazing if you are interested in WWII. I had him do writing assignments about each state. On what is their economy based? When and why did this state enter the Union? What are on-going issues in this area? We also used a program I bought, I think it was called Prodigy, in which we purchased a paperback book, and the program asked for essay answers to questions about the book. If you are not up on grammar and composition, don't feel bad. We are raising our granddaughter, and if you can type the question you had, you are better than many of her teachers. It just depends on how much time you are willing to spend with your own input. We usually did school in the morning, sometimes while I was driving, and incorporated museums, etc. whenever available. It is not that different from homeschooling in a sticks and bricks house. You just have a lot more options for outside activities. We had always been fairly structured in our schooling, so I continued basically in that manner. This was our last child, and the only one that I wasn't working full-time and being mom, so I really enjoyed it. He is now working in some computer job with a very high security clearance, and doing quite well. He has been to every state except Hawaii, and traveled most of Canada as well. I used what he was already interested in, and built around that. It wasn't all fun for him, but most of it was fun. You can whip out a day's worth of school in short order when it is individualized. It is also a good chance to interest your kid in something you like. I started reading "Lord of the Rings" - all four books with "The Hobbit" - aloud to him, and two years later when we finished, he immediately started reading the whole series over by himself.
More info than you wanted, but I do miss those days!