The Museum of Mathematics (@MoMath1) in New York City offers wonderful programs (including many free options!) for children, families, teachers, and math aficionados. A colleague of mine, Alé Cozzi, introduced me to Momath’s monthly Math Encounters series:
Math Encounters is MoMath’s popular free public presentation series celebrating the spectacular world of mathematics, produced with support from the Simons Foundation. http://momath.org/math-encounters/
At a recent-ish Math Encounter, I learned about the amazingness of Erik Demaine (@edemaine), who was the youngest math professor ever invited to join Massachusetts Institute of Technology (MIT)’s faculty. Besides juggling, knot theory, font creation, and origami, Erik demonstrated his Fold and Cut Theorem. Basically, you take a piece of paper, fold it in some amount of ways, and then make one cut. The results are remarkable. http://erikdemaine.org/foldcut/
Erik told the (potentially historically inaccurate) tale of Betsy Ross using the Fold and Cut method to create 5-pointed stars on the original American flag. I shared this with the 4th grade team, since they study Colonial America and fractions using polygonal shapes.
Here are (possibly) Betsy’s instructions:
Here is the template shared by Erik: 5PointStar