Thanks SydneyMathsJam. Combining Rule caused some self-kicking, and the cute melon problem was nice. Some over-complex solutions and some nice intuitive ones. Still working on the rectangle thing!
Also made some tetraflexagons.
10 Jammers in all.
14 people, which is close to a best we think.
Cracked the envelopes, and we *may* have a viable Fermi problem.
Ottawa MathsJam's gift of a nonogram proved very popular with the nonogram cult :)
Great times. Thank you @PaviaMathsjam. Good for tonight - and good to take home and finish. The 'Cut' was a big hit, and we've a few good origami fans who were pleased. :)