Pi Day lesson: (16/80/69)

If you look up the origins of Pi on Wikipedia you get this:

It was the 16th letter of the Greek alphabet, that's interesting due to Pi's gematria:

Every year PiDay comes 16 days after 2/27, 22/7=3.14 like Pi.

It also says Pi=80 in Greek numerals:

We have the day for Pi called PiDay:

It says Pi is from Greece and the Greek alphabet and it has gematria ties to both: