Soma Cube Shapes
How to read the diagrams
Each shape is shown as flat layers, bottom to top, because that is how you build it. A filled square is a cube that belongs to the shape; a dashed square is empty space. When you show a solution, every square is coloured and lettered with the piece that goes there, so layer 1 is what you lay down first.
What this is
The Soma cube is seven pieces that make a 3x3x3 cube, and the cube is only the beginning. The same seven pieces build a great many other shapes, each with its own difficulty.
Every shape here has been solved by computer and verified, and the solution counts are real. The cube has exactly 240 distinct solutions; the Zigzag has only 48. Fewer solutions means harder, because there are fewer arrangements to stumble into by accident.
Why a flat shape is impossible. Three of the seven Soma pieces are not flat, so no shape that is only one cube thick can ever be built. If you are trying to make a flat wall and failing, you are not missing a trick.
Print the challenges
The print button gives you a clean sheet of every shape with no solutions on it, which is the version worth having on a table or handing round a classroom.
If you want many more challenges than the ones here, Cube Alchemy is a curated set of 180 in one box. The background to the puzzle is in the Soma cube explained, and the wider range is in mechanical puzzles.