My favorite tetris piece

"My Favorite Tetris Piece", an original model by me, built using Sonobe modules.  The title is a joke because it's one of the few tetrominoes that is not a piece in Tetris.

This month I'm teaching a class on modular origami.  I don't know how many people will attend, or what age they will be.  It's supposed to be for kids, but maybe some of their parents will stick around.

Picking out models for kids is an interesting constraint.  Basically it has to be something simple and easy.  And short, don't forget short.  I'm honestly not sure whether the average grade school kid has a long enough attention span to make thirty identical units in one sitting.  Hell, even I don't ever make that many units in one sitting.  But for a class it has to be in one sitting.

Because I'm not sure how focused the kids will be, this presents yet another constraint.  I want models that can be big or small, depending on how the class goes.

The Sonobe modules are excellent for this.  They're easy to make.  If you combine 6 of them you can make a cube.  If you combine 12, you make an octahedron.  30 and you have an icosahedron.  Or you can make irregular shapes like the one above.  That one uses 18.  Part of the point is to inspire kids to be creative about what they do with the origami, but not make something so flashy that I outshine the kids.

For once, I timed myself.  Each unit takes a little over a minute and a half to make.  That's really fast!  Sonobe modules are just so easy.  It leaves time for more complicated models.