Tag Archives: Puzzle

The Three-to-Five Triangle Puzzle

The Three-to-Five Triangle Puzzle

This week’s Puzzle Corner activity comes out of a rich historical tradition that dates back to the 19th century when matches were first manufactured. Invented in 1827 by the British chemist John Walker, matches soon replaced the tinderboxes that people had formerly used to light fires. As matches grew in popularity and became ubiquitous later… Continue Reading

Locating Legs

Locating Legs

This week’s Puzzle Corner activity has a holiday theme. In it, students are presented with a paradoxical scenario and asked to try to make sense of it. In this scenario a child is hiding under a table at her parent’s holiday party. Looking out, she can count 20 legs and thus knows there are 10 adults in… Continue Reading

How to Make Your Own O’Beirne’s Puzzle

How to Make Your Own O’Beirne’s Puzzle

Last week I showed you the O’Beirne puzzle and 30 of you very quickly responded to the offer of a free puzzle. I hope you’ve gotten it by now. In future posts I’ll explore with you some ways to use the puzzle to engage students with Common Core Standards for Mathematical Practice as well as… Continue Reading

Further Explorations with O’Beirne’s Cube

Further Explorations with O’Beirne’s Cube

This post is a quick follow-up to the one from last Monday in which I showed you the O’Beirne cube puzzle. After we finished filming for that post, we still had the six puzzles on the table and we got to talking about the sequence in which the puzzle comes apart and goes back together… Continue Reading

O’Beirne’s Cube

O’Beirne’s Cube

This post is a bit of an experiment. First of all, I want to tell you about and show you a put-together-puzzle called O’Beirne’s cube. This is not just any puzzle. It is one of the most amazing, delightful, and elegant puzzles ever invented. There are people who know about things like this who rank… Continue Reading