3 transparent glass cups
Place the three glasses side by side.
Fill the first and third cup with water, but leave the center cup empty.
Select the two primary colors you want to blend from your assortment of food coloring options. Choose two primary colors that will mix to make a specific secondary color. For example, use red and yellow to create orange or blue and red to make purple.
Fold each paper towel square in half, in half (long length) again, and in half (long length) once more.
2 pieces of paper towel
Add several drops of one primary color to the first cup, and add several drops of the other primary color to the third cup. Do not add any food coloring to the second (middle) cup.
After about one half hour, you will find that the colored water has started traveling up the paper towel bridges and over into the empty middle glass.
After about two hours, the once empty glass will contain water from both glasses of colored water. The color of the water in the middle glass will be a mixture of the other two colors.
Leave everything in place for a while. Come back in about a half hour
You are probably aware that some colors, such as orange, purple and green, are created by blending certain primary colors (blue, red and yellow) together. You may also be familiar with the process, called capillary action, used by plants and flowers to extract water from the ground, transport it up through their stems, and distribute it to their petals and leaves.
By making the most of these two facts and using a few items from your kitchen, you can create a little magic by making water travel and colors change. The undertaking may seem complex, but it is quite simple and a whole lot of fun.
Place one end of one of the folded paper towel into the colored water in the first glass and the other end into the empty glass, like a bridge between the two glasses. Repeat the process by placing one end of the other folded paper towel into the colored water in the third glass and its opposite end into the empty glass.