In large saucepan, bring water and salt to a boil. Add jumbo shells, 3 or 4 at a time, until all are in the pot. Boil, uncovered for 10 minutes, stirring occasionally. Drain and cool on waxed paper or parchment paper, keeping them separated so they don't stick together. While shells are cooking, mix together ricotta cheese, cottage cheese, mozzarella, parmesan, egg whites, parsley, oregano, green onion, salt and pepper. Fill each shell with about 3 tablespoons of cheese mixture. Spread a thin layer of spaghetti sauce on bottom of glass casserole dish. Place shells, open side down, in dish and cover with remaining sauce. Cover with foil. Bake at 350 degrees for about 35-40 minutes or until hot and bubbly. Place shells, open end down, onto plate and garnish with freshly grated parmesan cheese.