May Your Pi Day Be Irrational

Today is 3-14, or as it is known to many a Math major, Pi Day.

Pi Day dot Org describes Pi thusly:

Pi, a Greek letter, is the symbol for the ratio of the circumference of a circle to its diameter. It is approximately 22/7 and is usually calculated to 3 digits, 3.14. With the use of computers, Pi has been caculated to over 51 billion decimal places. Pi is an irrational number meaning it will continue infinitely without repeating. The symbol for pi, , was first used in 1737 by William Jones, but was popular after it was adopted by the Swiss mathematician Leonhard Euler in 1737.

If you want to send that special someone a Pi Day card, do so here.

Math teacher Lavern Chirstionson wrote some Pi Day songs. Let's sing this one together:

Oh Number PI

Oh, number Pi
Oh, number Pi
Your digits are unending,
Oh, number Pi
Oh, number Pi
No pattern are you sending.

You're three point one four one five nine,
And even more if we had time,
Oh, number Pi
Oh, number Pi
For circle lengths unbending.

Oh, number Pi
Oh, number Pi
You are a number very sweet,
Oh, number Pi
Oh, number Pi
Your uses are so very neat.
There's 2 Pi r and Pi r squared,
A half a circle and you're there,
Oh, number Pi
Oh, number Pi
We know that Pi's a tasty treat.

Pi is without a doubt the most interesting of numbers. Its history is complex, its exact determination impossible.

If you were thinking, "yeah" I would like to know about Pi Day and the types of activities that I could do at home with my kids who are flunking Algebra, here are some links:

A Pi Day reference page from Math teachers in St. Louis.

Exploratorium celebrates Pi Day, and points out that it is also Albert Einstein's birthday.



A great gift is the Pi Necklace.

Other Pi Day gifts.

The official Pi Day Org has lots of links, including Pi to one million digits.

I, thanks to scientific calculators that kept me entertained during boring math classes, memorized Pi to 15 digits in high school.

What is your favorite story about Pi? Did Pi help you calculate the amount of aluminum you needed to make a soda can with a 3 inch radius? Did it help you figure out how much rubber you needed to make a new tire for your SUV?

Have a fovorite Pi joke? "How do you reason with Pi?" A: You can't. It's irrational.

Please share on this great day.