Categorizing Bad Rulers (subtraction, combinations)

Categorizing Bad Rulers (subtraction, combinations)

Categorizing Bad Rulers (MathPickle, 2021) Our factory is a bit lazy. When making a ruler we only make some of the notches. Such a ruler is either BAD or TERRIBLE. Is the ruler with notches at 0-2-5-7 BAD or TERRIBLE? With BAD rulers, choosing any two marks gives a...
Squirrel Nutkin (counting, patterns)

Squirrel Nutkin (counting, patterns)

Squirrel Nutkin (Richard Guy et al., The Inquisitive Problem Solver, 2002) The theme is chosen from one of Beatrix Potter’s animals. I grew up with these stories in Belfast so I’m pleased to have found the perfect mathematical home for Squirrel Nutkin. 😉...
Smileys (algebra, patterns)

Smileys (algebra, patterns)

Smileys (Daniel Hodgins & Mason Philips, 2021) The Julia Robinson Mathematics Festival has an app that offers a playful start: https://jrmf.org/puzzle/smileys/ I like this activity as an algebraic exercise. I have not proven the solutions presented in the video...
Bumpy Wheel (multiplication)

Bumpy Wheel (multiplication)

Bumpy Wheel (MathPickle 2022) Bumpy Wheel is a two-player game. Setup: Put an even number of dots in a circle. Copy this pattern so both players have it.  Rules: 1) On your opponent’s dots: Secretly place consecutive integers starting at zero. They can...