Happy Pi Day!

For those of you who didn't know, Saturday was Pi Day. And no, I did not misspell Pi. March 14th is 3/14, the first three digits of pi (3.14159...). Because it fell on a Saturday this year, I got to celebrate it twice: once with my students on Friday, and then again with Jeff on Saturday.

On Friday I put together a short hands-on activity for my students to explore pi. I brought in several round objects (like a container of salt and a soup can), and they had to measure the circumference and diameter of each object and then compute the ratio of circumference/diameter. For those of you who didn't know or may have forgotten, this is the definition of pi. I think it's really cool that you always get the same number when you divide a circle's circumference by it's diameter, no matter how big or small the circle is. Of course, the girls didn't always get 3.14, but we discussed how this was due to our inaccurate measuring tools (string and rulers).

The girls had a lot of fun with the activity. They were really energetic and competitive, because those who finished first got to eat first. Earlier that week, I took a poll for which kinds of pies the girls would like me to buy, and then I went and bought them on Friday afternoon, right before our activity. They were sitting out on the counter as an incentive for them to do the activity. It was a hit.

On Saturday Jeff and I made a banana cream pie. I had some graham crackers in the cupboard, so I decided to make a graham cracker crust rather than buy one. It was pretty easy. I've included the recipe at the end of the blog if anyone would like to use it.

I used a special pi pan that a former math teacher gave me as a wedding gift:

Here's Jeff crushing up the graham crackers:

Here's me pressing the crust into the pan:















And here's me pouring the banana pudding into the crust:















Funny story: the first time Jeff and I tried to make banana cream pie (I think it was for pi day last year, actually), we added the normal amount of milk to the pudding mixture. We missed the instructions on the box that tell you to decrease the amount of milk when you're using it for pie filling. The result wasn't banana cream pie - it was more like banana cream glop. Thankfully, we learned from our mistake and didn't repeat it this year.


Recipe for Graham Cracker Crust
1 2/3 c. crushed graham crackers (7-8 full size crackers)
1/4 c. sugar
6 Tbsp butter, melted
Combine ingredients and press into a 9 inch pie pan. If you are making a pudding pie, you don't need to bake it. If you are making a pie that you bake, you would bake it beforehand, but I didn't write down that part of the directions because I didn't need it - sorry. (You can Google it.)