Raising Dragons: Ziplock Bag and Pencil Experiment

Here’s an easy experiment using water, a ziplock bag and pencils.

We started by filling a sealable plastic bag with water. Then we added some food coloring to the water to make it more colorful and sealed the bag. Then I asked the boys to push the pencils through the bag. Surprisingly, as they pushed the pencils through the bag no water leaked out. This is because the bag is made of a polymer.  Polymers are made of long chains of flexible molecules.  When the pencil is poked through the bag, the flexible molecules move to allow the pencil to pass through and form a seal around the pencil. So cool! Finally, the boys loved pulling the pencils out and watching the water shoot out of the bag.

ages 6 – 8

Science Topics
1st Grade, 2nd Grade, 3rd Grade

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