When your kids are very young, the car seat and a pacifier or well-placed thumb can work wonders. Now that they're a bit older, long-distance traveling can be somewhat more complicated. Here are some suggestions that have worked for us when traveling with our kids.
Years of traveling have left me convinced that the four most important things to travel with are a jug of fresh drinkable water, a roll of paper towels and some zip-lock plastic bags in various sizes. Paper cups are also a good idea. The reason that I consider these things essential is that together they take the challenge out of a lot of little unexpected obstacles.
The torn cookie bag can be poured into the sturdier zip-lock bag, the sticky fingers can be washed, and the bird droppings can be removed from the windshield. The dirty restroom sink can be bypassed, the nosebleed can be stopped, and the coffee stain can be prevented. The more I travel, the more things I add to this basic list.
Refining this a bit, I also place about a dozen individually folded paper towel sheets into a zip-lock bag, add the juice of a fresh lemon and some water, and seal. These wet wipes are nicer than the commercial kind and aren't loaded with chemicals.
To make a large, sturdy trash bag, I take a large paper grocery bag and place it inside an opened plastic grocery bag. An easy to make and inexpensive trash bag — complete with handles and a plastic bottom. If it's a very long trip, you may want to take two. Used hand wipes, empty but drippy juice boxes and the occasional banana peel will not seep through to your car floor this way. This bag is usually strong enough to be emptied out at rest stops and reused.
Another good packing idea is to bring a pillow and small blanket for each child. A favorite stuffed animal or doll can be comforting, too.