Simple color mixing idea for a table or Science Center! All you need is a large tray, 4 sponges, 2 cups, Q-tips and 1/2 sheets of white paper. Dampen the sponges and squirt a color on each sponge. Place them in the corners of the tray. One cup gets the Q-tips, the other is for discards. When a child comes to the center challenge them to make the secondary color that's portrayed on the sign (orange, purple or green). When they do, challenge them to experiment and make as many different colors as they can!