Let's say you're a parent helping a Grade 1 child with their math, and they're subtracting eight from 17, using small items - counters - like Smarti ...

For example, 9 = 2 (1 2)+7, and 15 = 2 (2 2)+7. This week's GeekDad Puzzle of the Week is simple: what are the two smallest counter-examples that disprove this conjecture?

Let's say you're a parent helping a Grade 1 child with their math, and they're subtracting eight from 17, using small items — counters — like Smarties, multicoloured Rocket candies or Lego ...

Math educators share four ways parents can use counters, like candies or lego pieces, to lead ‘number talks’ that help kids develop an understanding of how numbers are related.