We spent several weeks mixing primary colors to make secondary colors. Here is our last experiment before moving onto fall colors next week. I prepared six glasses of water and then folded six paper towels in half until they were the right size and then folded again lengthwise. To make the paper towels fit better in the glasses I snipped off about an inch from each side.
Next I added the three primary colors to alternating glasses.
Just as class started we gathered around the experiment and placed the paper towels into the glasses. We saw some immediate reaction, but it took a full three hours to get the desired results.