The large 3D shapes at Geometry Point are made of 2D shapes,
Squares, Rectangles, Circles, Triangles, and Pentagons.
- How many different 2D shapes are there?
- Look at the shapes in the canopy, how are they the same as the big shapes below?
- How are they different?
The shapes on the canopy would fold up in to the shapes below, if you could fold them!
Each shape in the canopy is called the "net" for the cooresponding shape below.
There is an other idea for a net etched in the concrete around each shape.
Projects and Activities
Measure and cut out the 2D pieces to make your own 3D shapes
- How many different nets does each shapes have (how many ways can you put the 2D pieces together?)
- How do you know when you have found all of them?
Take home Activities
Make nets for the shapes with the cut-out models below. (These PDF flies also work with laser and craft cutters)
STL files to make the shapes with a 3D printer:
Penagonal Prism 3D printer STL file
Trianglular Prism 3D printer STL file
Mathematicians ask:
- How many ways can I fold and unfold shapes?
- How do I know that I have found all possible ways?
See MIT professors Eric Demaine's research folding research in action - this is his job!
