It depends on the kid, and I would have him look at the menus and ask what he thinks. If you aren't at a buffet or a "family style" restaurant, he can still order from the kids' menu at TS and CS (anyone can). At buffet or family style, you have to pay adult prices for a 10 year old no matter what he eats. If he looks at the menus and would still rather eat from the kids' menus, buying the adult dining plan for him would be a waste of money. If he looks at menus and prefers the adult entrees, then I would crunch numbers. Or if you are eating at a lot of buffets or family style, I would crunch the numbers - DP might still be worth it.