Flexagons are flat models made from folded strips of paper that can be flexed to reveal a number of hidden faces. They are amusing toys that have also caught the interest of mathematicians and paper crafters alike. We will be making one of the simplest types, called a trihexaflexagon, which can reveal six unique patterns. Here is a video of the flexagon in action. Click on the size button (to the right of the volume button) for a full screen view.
To make your own flexagon, you will need to print the flexagon template (a pdf file) in colour on legal (8.5 x 11 in) paper. Cut the template out.
Crease along all the diagonals and along the centre.
Turn the template over to the non coloured side. Add glue along the small side and fold in half along the centre line.
Fold the left side under to create a mountain fold between the blue and red triangles.
Fold under again between the blue and red triangles. This creates another mountain fold. Let the single layer flap sit on top of the existing paper.
Now glue the two single layer flaps together to enclose all the uncoloured paper.
Congratulations! You've just made a trihexaflexagon.