In a large skillet over medium-low heat, melt 3 tablespoons margarine. Add cabbage and onions. Cover and cook, stirring occasionally, until tender and browned.
Meanwhile, bring a large pot of lightly salted water to a boil. Add pasta and cook for 8 to 10 minutes or until al dente; drain.
Stir cooked pasta into cabbage and add remaining margarine. Stir in cottage cheese and sugar; cook until heated through.