Expanding Straw Wrapper

1. Expanding Straw Wrapper Materials: Paper straw wrapper; dropper; water What you do: Scrunch wrapper tightly, then drip water onto it. What students see: The paper 'worm' grows longer. Question: Why does the paper get longer? 2. Oil and Water Separate Materials: Clear jar; colored water; vegetable oil What you do: Shake jar and let it sit. What students see: Mixed droplets separate into layers. Question: Why do the liquids separate again? 3. Oil-and-Water Lava Lamp Materials: Clear bottle; oil; colored water; effervescent tablet What you do: Add tablet pieces to layered oil/water. What students see: Colored blobs rise and fall. Question: Why do the colored blobs come back down?

Predict → observe three demonstrations → compare what changed → choose independent activity station → cleanup/share. Guiding questions: Question: Why does the paper get longer? Question: Why do the liquids separate again? Question: Why do the colored blobs come back down?