This is a really easy recipe that my 6 year old helps make, so a teenger should be able to do it on her own. It uses basic ingredients.

1 lb. hamburger or Italian sausage or combination of both
1 jar (28 oz or so) spaghetti sauce
1 onion, chopped
1 (16 oz) bag spaghetti noodles or other pasta (great with rotelli)
1/2 lb. mozzarella cheese, grated
1/2 to 1 c. parmesan cheese

Cook meat with onion. Drain fat. Cook noodles using package directions (leave al dente). Mix meat, sauce, and noodles. Layer in greased casserole dish with mozzarella and parmesan. Cover with greased foil. Bake at 350 degrees for 30 minutes, uncover and bake 15 to 20 minutes more. Serve with Italian bread and salad.