Classroom mode

Run it in class

What does a line of reflection symmetry guarantee?

Show of hands — before you project anything

Predict: if I add a bump to only one side of this shape, what happens when we fold it? Then we fold.

  • 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: if I add a bump to only one side of this shape, what happens when we fold it? Then we fold.
  • Predict whether this shape that 'looks balanced' will actually pass the fold test — vote first, then check.
  • Predict how many fold lines a square has versus a rectangle, then test each line by folding.

Where it shows up in real life

  • Folding a paper snowflake or paper heart, where one cut mirrors itself across the fold
  • A painted blot butterfly where folding makes matching wings appear
  • Faces, leaves, and letters like A and M that are almost — but never exactly — mirrored

A prediction-first worksheet — no answer key.

zero prep · no login · any projector

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