Balloon Whistle
A loud whirring/whistling sound develops.
Teaching & key ideas
What you do: Place nut in balloon, inflate, then swirl balloon safely.
What students see: A loud whirring/whistling sound develops.
Why it works: The nut rolls around and vibrates the stretched balloon surface.
Question to ask: Why does spinning make sound?
Lesson flow
Predict → demonstrate → observe → briefly explain → ask: Why does spinning make sound?