Reader Marc Chamberlain sent this video in a bit too late to get in our advent calendar, but it’s about the 12 days of Christmas so we’re still cool, right?

# You're reading: Videos

### Video: Mathematical Christmas Present Wrapping

If you were wondering what happened with all the left-over wrapping paper from this morning’s post about wallpaper groups, Katie has made a YouTube video demonstrating some mathematical quirks of gift wrapping. Enjoy!

### Review: Unique polyhedral dice from Maths Gear

Our good friends at Maths Gear have sent us a tube of “unique polyhedral dice” to review. The description on mathsgear.co.uk says they’re “made from polyhedra you don’t normally see in the dice world”. My first thought was that we should test they’re fair by getting David to throw them a few thousand times but — while David was up for it — I’d have to keep score, which didn’t sound fun.

So instead we thought of some criteria we can judge the dice on, and sat down with a teeny tiny video camera. Here’s our review:

### Here’s a dude solving a Rubik’s cube in freefall

That’s all.

### Bread & Kisses

*Bread & Kisses* is a short film by Katherine Fitzgerald about a mathematician who discovers love – I know, I know, you’ve heard this one before – but it also contains a mathematician who moves to the Alps to get more skiing in, so it’s the most realistic film about mathematicians ever. It also features the emotion of love in a star turn as an epsilon term.

Although it contains the line, “you forgot the most important ingredient: love”, so don’t get your hopes too high.

### Matt Parker approximates π by weighing a circle

Stand-up mathematician Matt Parker has accepted our π approximation challenge. His method involves weighing a large cardboard circle.

So, how did that go? Fortunately, Matt got it all on video:

I think he deserves a *round* of applause for doing all that long division.

### Video: The Aperiodical’s π approximation challenge

As part of our massive π day celebrations, The Aperiodical has challenged me with the task of assembling a group of mathematicians, some bits of cardboard and string, and a video camera, and attempting to determine the exact value of π, for your entertainment.

The challenge, which was to be completed without a calculator, involved using known mathematical formulae for π and its occurrence in the equations of certain physical systems. In the video below, seven different methods are used – some more effective than others…

If you reckon you too can ineptly compute a value in the region of π (in particular, if you can get a more accurate approximation than the date of π day itself, which gives 3.1415), feel free to join in the challenge and see how close you get.