Preheat oven to 350 degrees.
Line cupcake pan with liners.
Prepare cake mix. Add cake mix, water, eggs, and vegetable oil to a bowl and using an electric mixer, mix at low speed for 30 seconds, then at medium speed for 2 minutes.
Add ¼ cup of the sprinkles and mix on low just until combined.
Pour batter into cupcake liners, about ½ full.
Bake for 15-20 minutes, until you can insert a toothpick and it comes out clean.
Allow cupcakes to cool on a wire rack.
Once cooled, add whipped topping and frosting to a bowl and mix with an electric mixer on medium speed for about 45 seconds.
Snip off the end of piping bag or corner of ziplock bag and insert the frosting tip.
Place bag into a cup and fold the edges over the rim.
Spoon frosting into bag, and pipe frosting onto cupcakes.
Refrigerate cupcakes, as the whipped topping will start to settle at room temperature.