Spread 1/2 C of spaghetti sauce in an ungreased 9X13 in pan. Layer with half of the ravioli, 1-1/4 c of sauce, 1 cup cottage cheese and 2 cups mozzarella cheese. Repeat layers. Sprinkle with Parmesan cheese.
Bake uncovered at 350 degrees for 30-40 minutes or until bubbly. Let stand for 5-10 minutes before serving.