1. Folding Flexagons Laurie Wern Overmann Southeast Missouri State University

2. Flexagons Invented by Arthur H. Stone in 1939 as a graduate student from England at Princeton when his paper didn’t fit in standard American notebooks. Other members of the “Flexagon Committee”: Bryant Tuckerman, John W. Tukey, and Richard Feynman Popularized in the 1950s and 60s by Scientific American contributor Martin Gardner

3. Use in the classroom? Cross-disciplinary Equity, all students can be successful Communicating mathematics, following directions Problem solving Informal experience with geometric and topological analysis of properties and characteristics of two dimensional shapes

4. Let’s fold some flexagons!

5. Flexagons are named according to the number of available “faces” and “edges”: (prefix for number of faces)- (prefix for number of edges) flexagon

6. Fold a tetra-tetraflexagon: All images are all from The 1 st and 2 nd Scientific American Books of Mathematical Puzzles and Diversions.

8. Fold a hexa-tetraflexagon:

10. Other Flexagons to try:

15. References Gardner, Martin (1959). The Scientific American Book of Mathematical Puzzles and Diversions. Simon and Schuster, NY. Gardner, Martin (1961). The 2 nd Scientific American Book of Mathematical Puzzles and Diversions. Simon and Schuster, NY.