Teach children about the science behind color by using a simple coffee filter and a spin art toy. Just put the coffee filter on the spinner and touch the center with a water soluble black marker to make a circle. Place a few drops of water onto the middle of the filter while it's still spinning. The centrifugal action spreads the water soluble marker ink out and allows the colors in the black to separate. The color black is made up of different colors combined and the action of the water on the spinning coffee filter separates the colors into different layers of the filter.
Take a coffee filter and fold it in half, twice. Draw a line 1 inch from the round edge of the filter with a green water soluble pen. Draw a line 1 inch from the other side of the round edge of the filter with a black water soluble pen. Don't let the lines touch. Secure the filter with a paper clip to the inside edge of a jar partially filled with water. Make sure the rounded side of the filter is touching the water. Keep it there for one hour before observing the results. Explain to the kindergarteners how the water soaks up through the filter which soaks the ink into the coffee filter and the colors separate. The Center of Science and Industry website explains that the colors settle in different places because certain colors stick to the paper faster than others.
For this simple but pleasing experiment, instruct the children to paint a colored arc on a coffee filter. Let the children copy a rainbow pattern displayed on an overhead projector. Next, take a watercolor brush and paint the arc with water to see the colors blend into one another. Discuss the different colors and how some new shades were created as the colors ran together. Explain that red, blue and yellow are primary colors and that new colors are created when we mix primary colors together.
Gather candies with colored outer shells. Pick out four or so different colors of candy and place each one on a small bit of foil. Place a dropper full of water on each candy and let it sit for a moment until the water is colored. Using a toothpick or eyedropper, place a dot of color from each candy on a separate coffee filter and label the filter with the color of candy. Place each filter into a small glass filled halfway with water, making sure the color drop is just above the water line. You may want to clip the filter to the side of the glass. Observe how the colors break apart and spread up the coffee filter at 15 minute intervals. Explain to the kindergarteners that the candy has different dyes to create shades of color and in the water the colors separate and slowly spread up the filter.