Preheat toaster oven to 350°.
Cut each bagel horizontally into 4 slices, using a serrated knife. Place margarine in a small microwave-safe bowl; microwave at high 15 seconds or until margarine melts. Lightly coat bagel slices with cooking spray, and brush with margarine.
Arrange bagel slices in a single layer on toaster oven pan. Combine sugar and cinnamon; stir well, and sprinkle over bagel slices. Bake at 350° for 12 minutes or until crisp. Remove from pan, and let cool completely on a wire rack. Store bagel chips in an air-tight container.
Note: Substitute cinnamon-raisin bagels for plain bagels, if desired. To bake bagel chips in a conventional oven, place bagel slices on a baking sheet. Bake at 350° for 15 minutes or until crisp.