Popper Toy Jumps After a Delay
It waits, then suddenly jumps.
Teaching & key ideas
What you do: Invert the popper and place it on a table.
What students see: It waits, then suddenly jumps.
Why it works: The stretched rubber slowly snaps back, releasing stored elastic energy.
Question to ask: Why doesn't it jump immediately?
Lesson flow
Predict → demonstrate → observe → briefly explain → ask: Why doesn't it jump immediately?