# Yellow Pigs Day

We’re tantalizingly close to “the theorem,” but today we take a break from complex analysis to talk about something much more exciting: Yellow Pigs Day.

Yellow Pigs Day is a holiday celebrated at Hampshire College Summer Studies in Mathematics (HCSSiM) every July 17th. For those who don’t know, HCSSiM is a 6-week summer program for high school students. There’s a lot of time spent doing math, but not exclusively. In past summers there have been bands, frisbee teams, bridge clubs, and the like. Those familiar with the program will undoubtedly realize that this explanation doesn’t do HCSSiM justice. It’s so much more than “just a summer of math,” but we’ll get back to it.

Yellow Pigs day usually consists of classes (as usual) a talk on the social/historical significance of the number 17, a cake shaped/colored like a yellow pig, singing of math songs (a.k.a., yellow pig carols) and an ultimate frisbee game between the current students and the staff/alumni. That’s right many alumni come back to the program to celebrate. Alumni (such as yours truly) tend to be quite fond of the program.

No doubt you think this program, and in particular, Yellow Pigs Day, is quite odd. You are correct. One of the many things I love about HCSSiM is how readily everyone embraces these oddities.

Thus far, I’m sure you don’t really understand the pure joy HCSSiM can induce in it’s participants (students and staff). Not being particularly eloquent myself, I doubt I can give you a good explanation, but let me attempt anyway.

The focus of the program is not learning math, but creating it. The staff are around to guide the students in a right direction (notice “a,” not “the,” as there can be many correct directions to pursue). Of course, the students aren’t creating new theorems that no one has seen before, but that doesn’t take away from their excitement as they discover it for themselves.

Sometimes, math can seem quite dry, but not at HCSSiM. Staff (and often students) take pride in being able to explain the mathematics in an exciting manner. This might involve a motivating story, or a humorous analogy. Let me give you a few examples:

• The proof for Euler’s formula (for planar graphs) is often described by pirates trying to attack the a castle displayed diagrammatically by the graph. How many walls must they destroy to be able to reach every room in the castle?
• Just yesterday, one workshop described Halls Theorem in the following analogy: Ollivander has 100 wands he wants, and 100 incoming Hogwarts students to give them too. Of course, not every wand will work well with every student. Obviously, if there’s any hope at a matching, every collection of $N$ students must be able to use at least $N$ wands. Is this enough?
• Students sometimes decide to use their own notation. This year, they wrote $\binom{n}{k}$ as a pacman symbol with the $n$ inside the packman, and the $k$ in the mouth. They pronounced the symbol “$n$ chews $k$.”
I’m really not explaining it well. The point is, HCSSiM has a way of making math fun and goofy without losing track of the mathematics. For your daily dose of HCSSiM, start reading Cathy O’Neil’s blog.

I can give nothing but praise to this program. As a student, it changed my outlook on mathematics. As a staff member, it challenged me to become a better teacher, to be creative (while still being accurate and appropriate) with my explanations. If you missed out on HCSSiM in high school, you should seriously consider applying to be staff. You don’t want to miss out on the best summer experience of your life.

Happy Yellow Pigs Day, all! Next year in Amherst!