Primary colors (red, blue, and yellow) are the source of all other colors. Secondary colors (green, purple, and orange) are created when two primary colors mix. If you freeze up colored ice cubes, you can experiment with color mixing as they melt. Combine cubes to make secondary colors, and if you’re feeling really creative, see if you can make tertiary colors (yellow-orange, red-orange, red-violet, blue-violet, blue-green, and yellow-green)! Heads up: This project will dye your little ones’ hands. We recommend using gloves or putting the colored ice cubes in plastic bags for mixing.