The Challenge: Make two different sizes of origami butterflies and then see what you notice and wonder about your pieces!
Materials Needed: At least two different sizes of square paper. (Can be obtained from non-square paper if you ask nicely.) Math conceptsyou could explore with this challenge: angles, proportions/ratio (particularly between length, area, volume)
The Challenge: Fold your very own Hyperbolic Plane from a simple piece of paper!
Materials Needed: A square piece of paper. Youtube instructional video below! Math conceptsyou could explore with this challenge: Algebra (how many folds per stage?), angles, counting, exponents, functions, geometry, Hyperbolic planes, proportions/ratios, sequences, symmetry, topology, vertices/intersections