Expanding Straw Wrapper

The paper 'worm' grows longer. Ask students to predict what will happen. Scrunch wrapper tightly, then drip water onto it. Key idea: Water enters the fibers and causes them to swell and straighten. Ask: Why does the paper get longer? Safety and cleanup: Use tray. https://www.google.com/search?q=%22Expanding+Straw+Wrapper%22+science+demonstration+experiment