Classroom mode

Run it in class

Where does a helium balloon go when you let it go?

Show of hands — before you project anything

Predict before we test: does a helium balloon float to space, float forever, or pop?

  • A Way more than you'd guess
  • B About what you'd guess
  • C Way less than you'd guess

Count the votes out loud. Hold them to it — then watch.

Project it (fullscreen)

Discussion prompts

  • Predict before we test: does a helium balloon float to space, float forever, or pop?
  • Predict: as the balloon climbs into thinner air, does it get smaller, stay the same, or swell up?
  • Predict: what pushes the balloon up — the helium inside, or the air outside?

Where it shows up in real life

  • Weather balloons that swell to house-size and burst near 30 km, then parachute their sensors home
  • Blimps and airships, which float on lighter-than-air gas but stay low on purpose
  • Deep-sea floats that 'fall up' toward the surface because they're lighter than the water around them

A prediction-first worksheet — no answer key.

zero prep · no login · any projector

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