Cut each tortilla into 6 wedges, and arrange in a single layer on a large baking sheet coated with cooking spray.
Combine sugar, cocoa, and cinnamon, stirring well.
Coat wedges with cooking spray; sprinkle half of sugar mixture over wedges.
Turn wedges, and coat again with cooking spray; sprinkle remaining sugar mixture over wedges.
Bake at 350° for 15 minutes or until crisp.
Combine whipped topping and yogurt, stirring well.
Arrange 3 tortilla wedges around 2 tablespoons dip for each serving.