There are a number of experiments on light and color that I'd like to do with the kids. Unfortunately, last week I just couldn't find the time to prep the experiments, so we ended up exploring colors (as well as capillary action) spontaneously using materials we had on hand. It ended up being a lot of fun. Here's what we did:
It actually started out as an art activity, where I invited the girls to draw on coffee filters, and the spray them down with water:
They enjoyed watching the colors spread out (I think this demonstrated capillary action and solubility as well) and observing the differences between drawing with markers on a dry surface vs. a wet surface. The paper towel that we put under the filters turned out pretty cool, but the filters were fairly muted:
While we had the markers out, I noticed that some of them had dried out, so I thought of another fun little activity. I brought out an empty ice-cube tray and put a little bit of water in each spot on one side. I invited the girls to dip the dried-up markers into the water to color it:
After we had some colored water, I gave them medicine droppers and showed them how we can use the empty ice cube slots for color mixing experiments. We made all of our secondary colors (orange, purple, green), and then I let the kids experiment with color mixing all on their own:
One experiment I remember from my childhood was separating colors from ink using capillary action. The kids helped me draw a little line with their markers on pieces of paper towels and dip the ends into some water. They enjoyed watching the water climb up the paper towel (they know that water flows down so they recognized this was an anomaly). I explained that this was the same process that plants use to bring water from their roots all the way up the stem to their leaves.
The experiment did not look the way I remember it from childhood (where you could really see the colors of the ink separate), and I think the difference is that all the markers we buy are 'washable'. The girls did observe some blue at the edge of the green and purple strips and some yellow at the end of the orange strip. They always enjoy the scientific process of trying out new experiments and making observations.