One more suggestion for you and the kids - go on craigs list or search other sources (you could even borrow) over the next couple of months for a camera for each of the kids, and let them chronicle Their Trip.
They can edit and create a blog or an album of the trip, while driving from one location to the next, this will help with the hours of driving time as you go from one location to the next. With the digital camera they will all have a Great Personal Diary of the trip, something they will appreciate more as they get older.
Both my boys still chronicle their trips (38&40) today, learning from the times we traveled with the little cheap box film cameras.
Just a thought,
