The Taby Tray has been a great joy for our car rides. It is basically a small tray - think airplane tray... it feels and pretty much looks the same - that straps to your child's car seat or stroller. This gives them a flat surface to write or color on, eat on, play on, while you are driving. It also has a fairly deep cup holder built in, which easily supported a Burger King King-sized cup during our drive. It has a lip around the entire edge as well, which is great for keeping crayons and other rolling items on the tray and off the floor. The bad thing about installing the Taby Tray is that you have to remove your car seat to put it in, but at least you only have to do that the first time. It straps underneath the seat, but after the initial install (took my husband like 30 second) you can leave the tray attached. It just sits to the side until you want to use it, so the child doesn't have to have it up all the time, only when he/she wants to use it. I just pull it across my child's lap and clip it in like a stroller seat belt buckle when my daughter wants to use it, and unclip it just as fast when she's done or we get to our destination. You can also use it on a stroller, but I haven't done this yet. So far my daughter has eaten a few snacks on it, kept her drink in it, and colored on it with both crayons and her Aqua Doodle. I have a convertible car seat, but I also think it would work just as well with a booster, though it might be harder with the booster not staying firm in the car unless buckled. Check it out... it just might be the thing you are looking for to keep your kid entertained in the car!