Coin Vortex in a Funnel

1. Coin Vortex in a Funnel Materials: Coin vortex/funnel or large funnel; coin What you do: Launch coin around the rim. What students see: Coin circles faster as it spirals inward. Question: Why does the coin move faster near the middle? 2. Capillary Tubes Rise to Different Heights Materials: Thin tubes/straws of different diameters; colored water What you do: Place ends in same water reservoir. What students see: Water rises higher in narrower tubes. Question: Why does narrower sometimes mean higher? 3. Thread Loop Opens with Soap Materials: Water tray; loose cotton thread loop; dish soap What you do: Float loop, touch soap inside loop. What students see: Loop snaps open into a larger shape. Question: What is pulling the thread?

Predict → observe three demonstrations → compare what changed → choose independent activity station → cleanup/share. Guiding questions: Question: Why does the coin move faster near the middle? Question: Why does narrower sometimes mean higher? Question: What is pulling the thread?