DemoTK

Pepper Runs from Soap

Pepper races away from the soap.

Teaching & key ideas

What you do: Sprinkle pepper on water and touch soap to the center. What students see: Pepper races away from the soap. Why it works: Soap lowers surface tension locally and the surface pulls away. Question to ask: Is the soap touching every piece of pepper?

Lesson flow

Predict → demonstrate → observe → briefly explain → ask: Is the soap touching every piece of pepper?