In this lesson I have kids create a puzzle cube in 123D Design. I use this software in my class because it is free and there is also an Apple App so the kids can use it on their iPads (every student in my school gets one free to use during the school year). You could of course adapt this to whatever 3d software you have chosen to teach.

Attached is a PDF document with instructions. You should start off explaining what a soma/puzzle cube is. Pass around a physical example if you have one. Since you might only have one 3D printer to use group up students and allow them to design the pieces.

Another thing I have them do is to create a solution guide when they are finished.

Chamfer or fillet the edges probably would be a good idea before printing. Although printing one square would be a good example where you could explain the design principle of part tolerance.

I then print the pieces and have them assemble it. Some sanding might be required to get the pieces to fit even after the fillet. Before I had a 3D Printer I bought foam/ wooden cubes and had them glue the pieces together.

Then I have them pass it to another student/group and have the student follow the solution guide to solve the puzzle.

The stl file is added just as a reference and is not designed to print. I encourage anyone who wants to to build their own to try out 123D Design.

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You will be creating a puzzle cube in 123D Design.

• This cube contains 27 cubes (3x3x3).
• Each cube measure 10cm3.
• The puzzle system must have 5 pieces.
• Each piece must consist of 4 to 6 cubes.
• No piece should be the same shape.
• The five piece must make be able to be assembled into a cube.
• Cube should interlock.
• At least 4 pieces should extend in the X, Y and Z direction. Only one flat piece allowed.
• Color each cube differently

When you are done create a solution guide to your puzzle. There should be 5 steps; each step adds a piece until the puzzle is complete. Take screen shots and paste them into a word document. Add text to the guide if steps need clarification.