Fun and Inspiring Pi Day Activities Everyone Can Enjoy!
Why should you never talk to Pi? Because they’ll go on forever!
We joke, of course. It goes without saying how much we love Pi Day here at MIND. Being one of the biggest math holidays of the year, we couldn’t let the month go by without offering up some of our favorite Pi Day activities! Not to mention it's another excuse to eat some pie.
Pi Day holds a special place in our hearts. In the past, we’ve featured some amazing pies from our MIND colleagues. Keep reading to see some of our past delicious Pi Day-themed pies!
Celebrated every year on March 14th, Pi Day is an opportunity for math-lovers worldwide to recite as many of the infinite digits of Pi as they can. How many Pi numbers can you recite? 3.14159265358… you get the idea!
What is Pi?
Pi, represented as “π”, is a symbol used to depict a math constant—which is the ratio of a circumference of a circle to its diameter: Pi = circumference/diameter (you still with us?). We call it a constant because the number Pi (π) is the same for EVERY circumference in the entire world. That’s why π is always equal to 3.14.
This is true for any circle—all circles of all sizes—because pi is a ratio, meaning that every circumference of a circle is about three of its diameters long, plus a little more. We can prove that this ratio scales for any circle.
Think of a Ferris wheel, the wheel of a bike, or a pie! What else can you come up with? Pi is also important in many STEM fields and wouldn’t be possible without Pi: aeronautical engineering, architecture, video game programming, you name it!
And guess what? Today is also Albert Einstein’s birthday! What are the odds? (Math enthusiasts out there, do your thing).
Learn more about the history of Pi here and explore more about the history of Pi Day here.
Pi Day Activities
Memorize as many Pi Digits as Possible!
Did you know that the current record-holder for reciting the most Pi digits is Suresh Kumar Sharma—he holds the record at 70,030 Pi digits!
Share the catchy Pi Song with your students below and see how many Pi digits they can memorize.
Discover Pi in Everyday, Ordinary Objects
For this activity, all you need is some yarn (or strings), scissors, and any round object. It could be a paper plate, an orange, a cup, or a round clock.
Find the hidden number in your chosen round object by:
Wrapping a string around the circular object.
Cut the string—this will be the circumference of the circular object.
Now take your string (circumference) and stretch it across the round object—the distance of the string across the object is referred to as the diameter.
Next, cut as many strings (diameters) as you can.
Notice, no matter what circular object you end up using, you should be able to cut three complete diameters and have a short piece of string left over. So cool!
Paper Plate Pies
Here’s a fun activity for the much younger mathematicians out there. Even if your students don’t understand the meaning behind Pi, they can still have fun with this activity where they’ll be introduced to circles and ratios.
All they’ll need are a few paper plates, colorful construction paper, crayons, glue, and safety scissors.
Your students can cut the paper plate up into little sliced pies and put them back together again! It’s a great way for them to learn about circles and even introduce them to fractions.
Pi Word Challenge
Pi Day celebrations don’t have to be limited to math teachers and math classes. Your students can hold a Pi-writing competition by writing as many words as possible that start with Pi.
Just set the timer for three minutes (or however long you want the challenge to be) and let the Pi-word competition begin!
Bake a Pi Day Pie!
What kind of Pi Day list would this be if we didn’t include baking actual pies? The best part, of course, is you get to eat them!
And how can we forget about our very own ST Math pie monster?
Pie monster is a sweet critter who has a passion for just two things in life: eating pies and helping you understand math. Why not celebrate this year's Pi Day by assigning some pie monster puzzles to your students throughout the week? If your students don't have an ST Math account yet, you can play with pie monster and explore two-step problem-solving here.
Why is Pi Irrational?
Pi Day is also a great opportunity to have rich discussions about and marvel at irrationality. Pi is just one specific, special irrational number. But there are so many more! In fact, there are infinitely more irrational numbers than there are rational numbers. But what does that mean?
Some questions you can think through with your students:
We know that pi is approximately 3.14…, so what two rational numbers can you bookend around pi to anchor it on a number line? 3 and 4; 3 and 3.5; 3.1 and 3.2; these are all fine answers.
How can you make that window smaller? Adding a place value is a fine strategy.
For however close two numbers are, what number(s) can you think of between them? Again, adding or tweaking a digit works.
What numbers do you think are directly on either side of pi?
For those numbers you thought of, can you think of another number that can fit in between them? Yes!
The ST Math puzzle “Number Line Zoom” is a great example of this idea—that you can forever zoom into a number line and find more numbers between numbers. Because we can always add another digit, or tweak a digit, the world of irrationality is truly infinite. Just the space between 3 and 4 contains its own infinity! Pi is one speck on that number line, alongside many more irrational numbers.
These are deep philosophical questions that you can introduce to and discuss with a wide range of students. Regardless of your age, it will probably hurt your brain all the same because you’re expanding into an abyss of endless numbers with endless digits. You know, eating some pie might make that headache go away...
If you decide to celebrate Pi Day this year, tell us all about it! Whether it’s one of the activities we shared here or another exciting Pi Day activity, please share with us on social media! Just remember to tag us (@stmath) on Twitter or Instagram.
Happy Pi Day, everyone!
About the Author
Victor Nguyen is MIND’s Content and Community Specialist. Victor is a passionate storyteller with a penchant for creative writing. In his free time, you can find him engrossed in books, going on long hikes, or trying to meditate.