Kaleidocycles and Hexaflexagons
Kaleidocycles are a three-dimensional paper sculpture you can turn around and round! Flexagons were first created by Arthur Stone at Princeton University in 1939, which were later published in 1959 to the general public in Scientific American.
These are simple to make and fun to play with. When I first showed them to my own kids, they immediately made one for each kid in their class, and also stumped the teacher that day when they asked how it worked. Please login or register to read the rest of this content.
The video below is made by Vi Hart, a smart and spunky mathemusician who has made amazing videos about the history of hexaflexagons that are fast-paced and fun.