# The calendar is full of odd holidays that can help you give what might be “just another day” a little spark.

National Hamburger Day? Yes, thank you. May the Fourth? Good reason to watch *Star Wars*. But did you know that there are also some great math holidays?

There are – and you should be celebrating them.

### 1. Pi Day

Pi Day is the quintessential math holiday. On Pi Day we celebrate pi, the constant that that tells us the ratio of a circle’s circumference to its diameter. March 14 written numerically is 3/14, as in 3.14, the first three digits of pi’s endless sequence of numbers.

On March 12, 2009 the U.S. House of Representatives passed a resolution declaring every March 14 “National Pi Day.” So, convince your teacher to buy you a pie in class and get the most out of this best-known math holiday.

### 2. Fibonacci Day

Here’s a day that should be celebrated by math lovers and artists alike. On Nov. 23 we celebrate the Fibonacci Sequence, a sequence of numbers that creates a spiral, beginning with 1, 1, 2, 3. That’s how we get to Nov. 23 (11/23).

One of the great things about Fibonacci’s sequence is that it’s frequently found in nature where spirals are encountered, making for endless applications and reasons to engage with the famed sequence.

There are no rules to Fibonacci Day, so draw a spiral, make a mural, or eat ice cream with a chocolate syrup swirl.

### 3. Pythagorean Theorem Day

Celebrate some triangles on this irregularly occurring holiday.

Here we celebrate the Pythagorean Theorem, which states the the length of the sides of a right triangle always adhere to the equation *a*^{2} + *b*^{2} = *c*^{2}.

So, the holiday occurs any time the date aligns to the Pythagorean Theorem. The next one will be Aug. 15, 2017. (8^{2} + 15^{2} = 17^{2})

Try to figure out the next couple of dates you can celebrate this math holiday after 8/15/17. (Hint: They will happen in 2020 and 2025.) Then go do some math problems, draw a right triangle, listen to Pink Floyd, and join a band where you play the triangle.

### 4. Sonia Kovalevsky Mathematics Day

This day doesn’t occur on any specific date and is usually just celebrated in schools. On this day we celebrate the life and career of Russian mathematician Sonia Kovalevsky to encourage young women to get involved in math.

She was born in 1850 and was the first major female mathematician in Russia. Read more about her amazing life here.

You can even use the holiday to celebrate other female scientists and mathematicians.

### 5. Math 2.0 Day

On July 8 we celebrate the intersection of math and technology. It’s a growing overlap that includes every device in your pocket or bag.

Early July is dominated by another holiday, so give Math 2.0 Day a little love and remind everyone to celebrate their math holidays – even if they’re tired out from days of fireworks and grilling in the backyard.

### 6. Mole Day

Mixing math and chemistry, Mole Day is a math holiday celebrating Avagadro’s number (6.02×10^{23}). It’s a basic unit of measurement in chemistry called the Mole.

The holiday is celebrated on Oct. 23 (10/23) from 6:02 a.m. to 6:02 p.m. The whole thing is fueled by puns – using mole sauce, whack-a-mole, and bevy of other mole-related jokes to pump up the party.

The National Mole Day Foundation themes each year’s celebration, with 2015 being “May the MOLES be with You.” Past punny iterations include “Molar Eclipse,” “Ride the Molercoaster,” and “Remember the Alamole.”

### 7. World Maths Day

While maths as a plural looks funny to Americans, this title comes from the day truly being global.

This math holiday is celebrated on March 1 of each year. It’s far less specific than many of the holidays above, and is aimed at getting people excited about math and interested in math-related jobs or fields of study.

If you aren’t sure what to do on World Maths Day, try out these fun math games.

Now, mark your calendar and go celebrate some great math holidays, or even try and make up your own with great breakthroughs in math history, like the newest prime number.

J. David BennettMay 11, 2017 at 1:39 pmYou left out Tau Day 6.28 . tauday.com

Carlo GravinaFebruary 12, 2018 at 11:47 pmpi isn’t an irrational number.

I can calculate the circle area without pi

Keeping it Real with Pi Day Activities - STEM JOBSMarch 6, 2018 at 9:56 am[…] many STEM observances that occur throughout the year. Mark your calendar and celebrate these other math holidays. Don’t forget to share your Pi Day activities and track other celebrations on social media […]

Brighten Up Testing Season with Math HolidaysMarch 13, 2018 at 11:02 am[…] math holidays you should celebrate. (2016, February, 2). STEM Jobs. Retrieved from http://stemjobs.com/math-holidays/ Learn about pi. (n.d.). Pi Day website. Retrieved from http://www.piday.org/learn-about-pi/ Pi Day. […]

Lessons from a Nerd Mom on Pi DayMarch 13, 2018 at 9:44 pm[…] Celebrate Pi Day, of course. Pizza Pie. Apple Pie. The options are delicious and plentiful. You can also observe Fibonacci Sequence Day on 11/23, Mole Day (10/23), Pythagorean Theorem Day (next will be 12/16/2020), or a bunch of others. […]