Ping-Pong Ball in Air Stream

1. Ping-Pong Ball in Air Stream Materials: Hair dryer on cool; ping-pong ball What you do: Point dryer upward and place ball in the stream; tilt slightly. What students see: The ball floats and follows the tilted air stream. Question: Why doesn't the ball blow away? 2. Vortex Cannon Puff Materials: Air-zooka or homemade vortex cannon; tissue target What you do: Tap the diaphragm toward tissue or light cups. What students see: A puff travels far and knocks objects over. Question: Can moving air have a shape? 3. Coffee-Filter Parachute Materials: Coffee filter; paper clip or small figure What you do: Drop flat filter and crumpled filter/weighted version from same height. What students see: One falls much more slowly. Question: Which shape catches more air?

Predict → observe three demonstrations → compare what changed → choose independent activity station → cleanup/share. Guiding questions: Question: Why doesn't the ball blow away? Question: Can moving air have a shape? Question: Which shape catches more air?