People with an interest in date coincidences are probably already getting themselves slightly over-excited about the fact that this month will include what can only be described as * Ultimate π Day*. That is, on 14th March 2015, written under certain circumstances by some people as 3/14/15, we’ll be celebrating the closest that the date can conceivably get to the exact value of π (in that format).

Of course, sensible people would take this as an excuse to have a party, so here’s my top $\tau$ recommendations for having a π party on π day.

### 1. Have a π (pie) bake-off

Baking pies to honour π day is a long-standing tradition, and surely this year you can pull out all the stops. Pies with digits of π on, pies in the shape of π, three whole pies and a little pie – the possibilities are as endless as the string of digits after the decimal point in π.

### 2. Decorate your house/office/classroom with π

Of course, no party is complete without decorations – cut out the symbol π and hang it around the room, or find some spherical balloons and write the formulae for the surface area and volume of a sphere on them with a Sharpie. Or, if you’re feeling productive, why not print out Think Maths’s Mile of Pi (or, you know, the first few metres of it) and stick it up around the walls?

### 3. Decorate yourself with π

There’s plenty of π-related tshirts out there, and the impending date-coincidence-pocalypse has caused an explosion in the availability of π tshirt designs. Aside from the official Pi Day website, there’s a special page on Spreadshirt, one on Zazzle, and even one on Etsy, which includes lovely badges, wall hangings and jewellery adorned with the magic number. If you’re feeling really serious about your love for π, why not get a tattoo? (Or a temporary one, for you and all your friends.)

### 4. Watch some YouTube videos about π

Good old Numberphile has plenty of videos about π, all collected onto one handy page, while Vi Hart has a playlist of all her pro- and anti-π videos.

### 5. Pun relentlessly about π

Get some friends ROUND, sit in a CIRCLE, and CONSTANTly make puns about π. It might seem IRRATIONAL, but I assure you it’s completely NORMAL. (Proof pending)

### 6. Have a π-related movie night

As well as the obvious, Darren Aronofsky’s surrealist psychological thriller π, you could watch other mathematical movies, or event just settle for things with the word π in their name, like The Life of π, Sπderman, or πrates of the Carribean. Or anything with Brad πtt.

### 6.0283… Post loads of cool content on The Aperiodical

This only counts as 0.283… of a suggestion, since it’s more something we’re doing than you – but we here at The Aperiodical will be posting a selection of π-related pieces, including articles, videos and interactive posts, from our own team and a selection of special guests. They’ll be going online in the lead-up to π day itself, and on the day we’ll post a round-up so you can find them all in one handy place.

So there you have my top $\tau$ suggestions for what to do on π day. Hope you have a ball (with volume $\frac{4}{3}\pi r^3$)!

The best way to celebrate — lobby the Parliament, the Government and the Bank of England demanding to mint and issue in circulation a coin of £$\pi$ denomination, to pay for various round goods — like pizzas, say, or car tires.

Also see Pi videos at Tipping Point Math

https://www.youtube.com/user/TippingPointMath