Preheat oven to temperature suggested on mix box. Prepare cupcake pan with liners. Prepare cake mix batter as directed.
Divide into four medium bowls. Add drops of food coloring to each bowl, until desired colors are reached.
With a spoon, layer the four colored batters, one on top of the other, in the cupcake tray. For example: a spoonful of blue, then pink, then, yellow, then green. There's no need to swirl the batters together—it'll happen while baking.
Bake as directed; remove and let cool. Frost and serve. Makes 24 cupcakes.