HEAT oven to 350°F. Prepare cake mix according to package directions using the water, oil and eggs. Line muffin pan with paper baking cups. Fill cups 2/3 full with batter. Bake 18 to 22 minutes. Cool completely.
COMBINE boiling water and fruit-flavored gelatin in small bowl. Stir 2 minutes or until gelatin is completely dissolved. Poke holes in top of each cupcake with a straw. Spoon about 2 teaspoons dissolved gelatin over each cupcake.
REFRIGERATE 2 hours. Spread with whipped topping. Decorate with sprinkles. Store loosely covered in refrigerator.