1. Preheat oven to 400°. Place the pitas on a baking sheet. Spread 3 tablespoons of tomato sauce over each pita, and let your kids do the rest: Sprinkle each pita with 3 tablespoons shredded mozzarella, 1/4 cup chicken, 1 teaspoon grated fresh Parmesan cheese, and the remaining tablespoon of mozzarella cheese; then top with veggies (optional).
2. Bake 10–12 minutes, or until the pizza is heated through, cheese is melted, and bread is crisp on bottom.