My grandma always used to play the ABC game with my cousins, sister, and me in the car. It would definitely work anywhere. Each person takes turns going through the alphabet. You have to think of a name, place, and food that starts with whatever letter you get.
Example:
Person #1: Hi, my name is Abbie, I live in Alabama, and I like to eat apples.
Person #2: Hi, my name is Brandon, I live in Buckingham Palace, and I like to eat bread.
Person #3: Hi, my name is Charlie, I live in Chicago, and I like to eat cheeseburgers.
You get the point.
It really does pass the time with kids.
What about a guessing game? I just thought of this one. You could call it something like, "Where's Mickey?" One person chooses, in their head, somewhere within that theme park that Mickey is. Each person gets two guesses and has to move on. You'd want to start with the main "land" and then try to guess within.
Let's say I picked that Mickey is on the Astro Orbiter.
Person #1: Fantasyland? Main Street?
Nope!
Person #2: Adventureland? Frontierland?
Nope!
Person #3: Tomorrowland?
Yep!
Person #3: Buzz Lightyear's Space Ranger Spin?
Nope!
Person #1: Space Mountain? Cosmic Rays?
Nope!
Person #2: Astro Orbiter?
Yep!
That person wins and gets to pick where Mickey goes next.
I tend to be able to think this stuff up pretty easily. It's all part of my teacher super powers.