Preheat oven to 375 degrees.
Cook shells according to package directions.
in a large skillet brown sausage and ground beef, breaking into small pieces as you brown. Place browned meat in a large bowl. Drain all but 1 T grease from the pan.
Add onion and garlic to same pan and cook over medium heat until translucent but not browned. Add to same bowl as the meat.
Mix meat and onion with bread crumbs, parsley, and oregano.
Make the cheese mixture by mixing the cottage cheese, shredded cheese (all but a 1/2 cup), Parmesan cheese and Italian seasoning. Mix in spinach.
Spread a small amount of marinara in the bottom of two 9x9 inch pans.
Fill each shell with about 2 T of filling. Place 12 filled shells in each pan.
Cover shells with remaining marinara.
Sprinkle on reserved shredded cheese.
Bake for 25-30 minutes until sauce is bubbly and the cheese if melted and lightly browned. If frozen, thaw and then bake for 35-45 minutes, cover for the first 25 min.