Themes · wave 2
The Möbius Strip
Paper, glue and scissors, and the first steps into topology: the part of geometry that does not care about lengths and angles, only about what is joined to what. Build each model on screen, then make it from real paper and check.
Gems
One Side, One Edge
Glue a paper strip with half a twist and it loses a side. Draw along it and count.
Cut It Down the Middle
Cut a ring in half and you get two rings. Cut a Möbius strip in half and you get… one.
Two Rings Crosswise
Glue two rings at right angles and cut both. Plain rings give a square; Möbius strips give hearts, sometimes linked.