Quite a few unusual math videos have come down the pike recently, so I thought I'd round them up here and share them with you.

Most of these include material I've rarely, if ever, come across before.

Over in the Mental Gym, I teach how to square 2-digit numbers. If you've mastered that, you may have wondered about going beyond 100. In the following video, you can learn how to handle squaring the numbers 100 through 199 quite easily:



Part 2, available here, teaches how to square the numbers 200-999. There's also a part 3 that teaches additional techniques, including how to handle some 4 digit numbers!

There are also a few old friends of Grey Matters have recenly-posted videos with math tricks.

This week's Scam School features a feat where you can determine how many cards are cut from a deck of cards. Where's the math? It plays a hidden role, as Brian Brushwood will explain:



The other old friend is Arthur Benjamin, whom you may remember from his popular TED video, or from my recent mention of his free video lecture on memorizing numbers. The newest post is his full hour-long Secrets of Mental Math lecture (More than 4 times longer than the TED video), based on his book of the same name: