How to Make a Tetrahedron?
It is simple to make a tetrahedron. You will need a small envelope (not the long business type envelope), a ruler, a pencil, and a pair of scissors. You should first fold the envelope in half, making sure it has a good crease. Unfold it and mark the envelope using a ruler from the upper left corner diagonally to the lower right corner. Repeat on the other corners. Fold along the lines and open back up. Remove the flap and the upper triangle. After this you can start folding until it resembles a pyramid and you have created a tetrahedron. You can find more information here: http://tremor.nmt.edu/activities/origami…
