With pi being approximately 3.14, annual pi day is March 14th.
But since pi is also approximately 22/7, pi day could also be July 22.

With pi day falling on Sunday, 3.14.2021, and many gifted students having a keen interest in math, here are a few thoughts on celebrating and exploring the unique number, pi:

1- mash-up math -
https://www.mashupmath.com/blog/tag/Pi+Day+2021

2- New York Museum of Math -
https://momath.org/pi-day-2021/

3- Wikipedia -
https://en.wikipedia.org/wiki/Pi

4- Guinness Book of Records - most accurate calculation of pi -
https://www.guinnessworldrecords.com/world-records/66179-most-accurate-value-of-pi

5- Guinness Book of Records - most pi digits memorized -
https://www.guinnessworldrecords.com/world-records/most-pi-places-memorised

6- Controversy alert: Another person may have memorized and recited more pi digits, although this has not been verified by Guinness Book of Records -
https://www.theguardian.com/science...on-world-record-japanese-akira-haraguchi

7- pi day history -
https://www.piday.org/

8- Many people choose to share a pie on pi day.
For a 12 inch diameter pizza pie, the circumference is approximately 37.68 inches.
To cut the pizza into 12 equal servings, each slice would have about 3.14 inches of the crust edge.
A "pi" size piece of pie!
For an 8 inch diameter dessert pie, the circumference is approximately 25.12 inches.
To cut the pie into eight equal servings, each slice would have about 3.14 inches of the crust edge.
A "pi" size piece of pie!

Plan now to enjoy making a special memory on pi day.