Mix the Kool-Aid powder, sugar, and cold water in a small bowl until the sugar and powder are fully dissolved, creating a vivid, fragrant syrup.
Add the crushed ice to the blender, then pour the Kool-Aid syrup over the ice.
Blend the mixture on high until it reaches a smooth, slushy texture, with the ice finely crushed and evenly mixed in.
Stop blending when the mixture looks vibrant, frosty, and slightly thickened, with no large ice chunks remaining.
Pour the slushie into chilled glasses, allowing the colorful mixture to mound slightly above the rim for visual appeal.
Enjoy immediately with a straw or spoon, savoring the cold, fruity flavors and icy crunch.