For this magic milk experiment, partly fill a shallow dish with milk, then add a one drop of each food coloring color to different parts of the milk. The food coloring will mostly stay where you placed it. Next, carefully add one drop of dish soap to the middle of the milk. It’ll cause the food coloring to stream through the milk and away from the dish soap. This is because the dish soap breaks up the surface tension of the milk by dissolving the milk’s fat molecules.
Invisible inks either react with another chemical to become visible or else weaken the structure of the paper so the message appears if you hold it over a heat source. But we're not talking about fire here. The heat of a normal light bulb is all that's required to darken the lettering. This baking soda recipe is nice because if you don't want to use a light bulb to reveal the message, you can just swab the paper with grape juice instead.
Find out how plants “drink” water with some food coloring. Use carnations, roses, or stalks of celery submerged in the colored water and watch the liquid slowly seep through the plant’s “veins” and towards the leaves. Keep an eye out -- you could have a very colorful bouquet just after the first day. Get the rundown by Dad’s Book of Awesome Science Experiments over here.
You won’t want to do this experiment near anything that’s difficult to clean (outside may be best), but kids will love seeing this “elephant toothpaste” crazily overflowing the bottle and oozing everywhere. Pour the hydrogen peroxide, food coloring, and dishwashing soap into the bottle, and in the cup mix the yeast packet with some warm water for about 30 seconds. Then, add the yeast mixture to the bottle, stand back, and watch the solution become a massive foamy mixture that pours out of the bottle! The “toothpaste” is formed when the yeast removed the oxygen bubbles from the hydrogen peroxide which created foam. This is an exothermic reaction, and it creates heat as well as foam (you can have kids notice that the bottle became warm as the reaction occurred).
Science is a wonderful thing for kids! There is so much to learn and discover right around us. Many science concepts start in the kitchen with simple materials you already have on hand. Fill a plastic tote with easy to find supplies and you will have a homemade kids science kit filled with learning opportunities that are sure to keep them busy all year long!