This morning Jena, Jenna, and Peter gathered the preschoolers around a clear tub of water and asked them to examine some everyday items that had been collected from around our classroom. The teachers asked them and to share their ideas about which of the items they thought would float and which would sink.
First we passed each item around and asked the children to make observations.
Is this object smooth or rough? Does it feel heavy or light? Is it small or large, thin or wide?
What do you think it is made out of? For example, is it wood, metal, paper, or rubber, etc.?
We then asked them to hypothesize about each of the items.
Did they think that the wood semi-circle would sink to the bottom or float to the top? How about the magnetic rock? The piece of paper? The rubber band? The tiny rubber baby?
The preschoolers had many ideas about why the items might float or sink.
Kaya- It's going to sink it down to the bottom cause it's going to stay at the bottom.
Anna Lee- I think it's going to go down to the bottom and then float back up to the top.
Austin- It's going to sink because it's heavy.
Nolan- It's going to float because it's squishy.
Jackson- I think it's going to float because it's light.
Zoe- It's going to sink.
Eva- It's going to sink if you throw it down really hard. Then it will go to the bottom and not come up.
Lena- Definitely sink because it's a sinking thing.
Jackson- It's going to float because it's small and it's rubber.
After making predictions about the items together as a group, the preschoolers each had an opportunity to test the items individually. They also tested new theories about how the item was placed into the water.
If they threw it in really hard, would it still float?
If they placed it in very gently, would it still sink?
What if they held it down on the bottom and then let go?
They were surprised to notice that some of the items, like the paper and the rubber band, both floated and sank depending on how they were placed into the water and how long they were in the water. They shared many ideas about why they thought these items behaved differently than some of the others.
We placed each of the items into one of two piles, the sinkers and the floaters. Jackson suggested we create a third pile for the "in-betweens", like the paper and the rubber band, that sometimes sank and sometimes floated. Some of the items, like the rubber baby, sank to the bottom first but then came right back up!
We decided to see if we could make one of the floating items sink by piling on other items that typically sank on top of it. This plastic lid, "our boat", floated on the top of the water. One by one, we added items on top of it until it eventually (much to the children's delight) sank down to the bottom.
When we were finished with our group observations, some of the kids decided to make their own discoveries too. As facilitators of learning, the teachers never told them why some items sink and why some float. Most of the preschoolers are too young to understand or retain the scientific reasons anyway. They will learn those answers in time.
Preschool children simply need to explore materials on their own, with our gentle guidance. They are naturally little scientists, eager to make their own discoveries about the world around them.
