My kids (DS19, DS18, DD15 DS2) played travel bingo. You can print cards from most online sources. We had one set my mom had made that they could use erasable markers.
We had the kids atlases (rand mcnally) and those were good. Also, I ordered travel guides before the trips and then cut out places they might see. As they were older, they were just given the guides when we stopped at the state rest stops.
DD15 suffers from car sickness so had to pack benedryl for her to rest better. She can't read or color, but she can watch movies on larger screens.
Cameras for them to take their own pictures..we have had pictures of clouds, the other sibling's nose, but it was all fun to look back at.
I think you will be fine. Many folks swear by the "state line gift" and I think that will be something I will do for our next trip.
We drive everywhere..and they are all planning driving adventures when they have their families. Well, not the littlest one yet, but there is still time and he loves his car seat!
I don't know the route you are taking as we haven't driven it, but we have stopped in SC to see the giant peach water tower, Charlotte NC has a giant baseball water tower, Metropolis IL has a giant statue of Superman. I am sure your route will have a surprise along the road, even if it's "how many chik-fil-a cows can we find"
Enjoy your trip!!
