A great car conversation starter is to count how many of something you see on the way to where you are going. For example, counting how many pizza places you see or how many red house.
We like to name how many things in a category you can count. For example, how many vegetables or fruits can you name. It’s fun to time yourselves and then count up the list. In the case of some lists it can also opens a bigger conversation like which veggies or fruits your like on the list vs. dislike. You can do this with anything- people’s names, cartoon characters, things that are a particular color, etc.