Sonobe Modules

Project taught by Dr. Eva Szillery at the Downtown Education Collaborative in Lewiston, ME.
This module was originally designed by: Mitsonobu Sonobe
For more information about Sonobe Modules:

The Sonobe Model shape can be used to create a cube, a stellated
octahedron, or a stellated dodecahedron.  In the picture below, you can
see a finished Sonobe Model Unit (left) and a cube (right) that can be
built using six of those units.
The stellated octahedron (below) requires 12 units.
The stellated dodecahedron (below) requires 30 units.

To make the Sonobe Unit:
Step 1:  Fold paper in half to form a mountain fold as shown below.
Step 2:   Fold bottom edge up to the mountain fold, and top edge down
to the mountain fold.  Then unfold, as shown below.
Step 3:  Fold the right top corner down, and the lower left corner up
as shown below.  Be sure that the triangles you create in these folds
line up with the parallel folds on the square.
Step 4:  Fold the top edge down to the center crease, and the bottom
edge up to the center crease, leaving the corners tucked under as
shown below.
Step 5:  Using the hypotenuse of the small triangle as a guide, fold the
bottom right corner up.  The left edge of the larger triangle formed should
be perpendicular to the bottom of the rectangular shape you started with.
See below:
Step 6:  Fold the top edge down to form a parallelogram.
Step 7:  Tuck the loose ends in to form an envelope.  This is like the
process you can use to close the top of a cardboard box without tape!
Step 8:  Turn the parallelogram over as shown below.
Step 9:  Fold to create a "mountain fold" in the parallelogram in such a
way that you form two congruent triangles with the fold as shown below.
Step 10:   Fold each of the two triangles so that the hypotenuse of each
is bisected, creating four congruent triangles.  the center "square" should
pop out toward you, and the two side triangles should have bends inward
as shown below.
Finally, make the number of units you need for the project you wish to
build.  Be sure ALL of the pieces stack neatly on top of each other.
They must be identical in order to be used for building!
See below: