Prepare the red jello according to the package directions. Divide the jello between your cups and place them in the fridge to chill until the jello has fully set (about 2 hours).
Once the first layer has set, divide the Cool Whip between the cups. Smooth the top of the Cool Whip using an offset spatula or a spoon. Transfer the cups to the fridge to chill again-- about 2 hours.
Prepare the blue Jello according to the package directions. Place the blue Jello in the fridge for about 15 minutes. You don't want it to start to set, just to cool down a bit. Divide between the cups and place them back in the fridge to set completely (about 2 hours) and ready to serve.
Serve chilled. Top with red, white, and blue sprinkles before serving, if desired.
Notes
The size of glasses/cups you use will determine how many servings the recipe will yield.Store covered with plastic wrap in the fridge for up to two days.