In advance of the party, roll out the biscuits or rolls very flat between sheets of waxed paper and store on a cookie sheet in refrigerator. When it's time to bake, set the oven at the temp on dough pkg (usually 350-425 deg F) and pour the sauce into a bowl that can be reached by all. Set out the cheese and other toppings (anything you think the kids will like, or nothing if you think plain cheese is enough), give each child 2 pizzas on a paper plate, arm them with spoons, and let them make their own. You collect the pies, put them on baking sheets, and try to remember whose is whose.
Note: You can use English muffins instead of dough. Allow 1 muffin per child as the base for the pizza.