I drive every year from NJ to Disney World. 17 hours in the car was torture at first, but it's a lot better now.
Here's some ideas:
1. Sleep. I usually sleep for a good 12 hours of the trip. I get car sick, so I take a dramamine pill, which makes you drowsy and I sleep for almost 12 hours total. You can get a dramamine pill at any CVS or Walgreens or Walmart. Even if you don't get car-sick, it helps you sleep.
2. 20 questions.
3. License plate game: Bring a notebook and each time you see a license plate from a different state, write it down. If you don't get all 50 on the ride there, continue it on the ride home. Some are tricky, like Hawaii and Alaska, but they aren't impossible!
4. Billboard game: In a notebook, divide the passengers in the car into two teams. Start with letter A. As soon as you see a billboard with the name of a restaurant, gas station, hotel, or anything that starts with the letter A, write that letter under the team that calls it out first. Once you complete the alphabet, whichever team won the most letters, wins.
5. Headphones and music.
6. Snacks.
7. If you have a TV in your car, bring DVDs!
8. I write, so journals and a pen would be good to bring. Keep a diary of your vacation.
9. Apps on your phone. (Subway Surfers is my favorite game)
10. Magazines and books.
Have fun!!!