By George Hart for the Museum of Mathematics

Here’s a challenge: Make something cool from binder clips.

It will be tough to beat this spherical construction by Yang Enqi. Using one handle, five clips of one color are linked cyclically into a pentagon. Using the other handle, twelve of these pentagons assemble like a dodecahedron to make the sphere. The above image is centered on a 3-fold joint, where three pentagons meet using one of the handles. The image below is centered on one of the pentagons, made from the other handle. Every clip has one handle in each of these two arrangements.

Notice that just six colors are used for the twelve pentagons, with opposite pentagons having the same color.

**More:**

- Math Monday: Twirligami
- Math Monday: Found objects
- Math Monday: Kirigami polyhedra
- Math Monday: Mathematical lathe work
- Math Monday: Modular Kirigami
- Math Monday: Mathematical beading
- Math Monday: Nailbanger’s Nightmare
- Math Monday: Recycling soda bottles into icosahedra
- Math Monday: Two-layer geodesic spheres
- Math Monday: What to make with golf balls?
- Math Monday: Knitted cellular automaton tea cosy
- Math Monday: Whittling links and knots
- Math Monday: Magnet constructions
- Math Monday: Hexagonal stick arrangements
- Math Monday: Paper plate geometry
- Math Monday: 3D Hilbert curve from plumbing supplies
- Math Monday: Math-play with your food
- Math Monday: Mathematical art in the lava
- Math Monday: Balloon polyhedra
- Math Monday: Sierpinski tetrahedron
- Math Monday: Skewer hyperboloid
- Math Monday: Morton Bradley sculpture
- Math Monday: Tetraxis puzzle
- Math Monday: Giant burr puzzles
- Math Monday: Fractal polyhedra clusters
- Math Monday: Giant SOMA puzzle
- Math Monday: Tie your bagel in a knot!
- Math Monday: Playing card constructions
- Introducing “Math Monday”

And I guess that’s 30 total binder clips.