Water on a Penny
First the students predicted how many drops of water they could put on the surface of a penny before it overflowed. Everyone was surprised by how many drops they were able to put on. Next, we smeared a thin layer of dish detergent on the penny. How would this effect the number of drops of water that would stay on the surface of the penny? Ask your student! Now that we have gathered this information we are trying to understand why these things happened and to draw conclusions from our experiment.
Taking in Water
Our second experiment was designed to help us think about why some objects take in water and others do not. Students put a dropper full of water onto a variety of objects to determine if they kept out water, took in some water, or took in all of the water. The objects were a micro-fiber towel, cotton ball, sponge, newspaper, plastic wrap, Kleenex, play-doh, and wax paper. We looked at the more porous objects under a magnifying glass. Our 4th grade scientists will be busy trying to figure out why the Kleenex was absorbent but the wax paper was not.