We're about to go on a long trip as well- I'm going to copy and paste what I wrote for another thread

My girls are 3 & 16 months and we're driving about 13 hours. Our first long trip!
We're leaving friday for a trip. We're planning on letting DH come home on Friday and sleep for two hours or so while I take the kids somewhere to get worn out. Then we'll ship out, we have two who sleep pretty well in the car so that is our hope. Then when DH gets tired we'll stop at a hotel and let everyone get more sleep. I figure me and the kids can go to the pool in the morning to let DH sleep even longer. I hate to drive so I'll do anything to help him feel rested! We hope not to leave until near nap time. But still, I'm sure there will be plenty of awake time since it is a 13 hour drive.
We bought a TV for the car- we don't have one at home so I think this will really keep their interest. We got it used off ebay for a good deal. I also bought some mini toys - kinds we don't have at home- so hopefully they will be really interested in them. A mini magnadoodle, mini bumble ball, those "peek inside" blocks. I really hope these little toys help spice up the ride. I'm planning on giving them a new one every hour or so. rotating them.
I'm vegetarian so there isn't a lot fo fast food I want to eat- so I'm trying to take as much as possible. Lots of dried fruit- dried pinapple (basically candy) even. the co-op has so many varieties and we just basically grabbed one of each. I'm ashamed to admit that fruit leather would be no "special treat" so we're leaving that at home- but it is a great idea if yours isn't used to it. I'm taking the fruit & nut granola bars, shelled pistachios, coconut crackers fromt eh asian food store, some trail mix (I think I'll add raisins, almond slivers, cashews, sunflower seeds, japanese crackers, and a few pieces of chocolate even), I'm going to make some "hearty" biscuits with tofu sausage & cheese baked in, and hopefulyl some other stuff if I can think of more.
So basically we are doing lots of snacks, new toys they've never had, kids TV and kids music (which they usually have int he car, so nothing new).