Pi for Kids!

Happy π Day!!! I am a huge fan of Pi! I'm pretty sure I still hold the record at my old high school for Most Memorized Digits of Pi: 279! :-) I had braces that year and for the colored bands on them that month, I assigned each number a color and then had the colors put on my braces in order. Let's just say I wasn't in the "cool club" during high school...I did get my extra credit, though...ha!

I have always loved numbers! For as long as I can remember I've loved patterns in numbers, putting numbers to music, and just messing around with mathematic symbols to make fun things. But kids don't fall in love with numbers very often (most of the time, through no fault of their own--but talking about the way our education system teaches math is for another day!). So I thought that I would take today, it being a math kind of day, to share an awesome way to teach kids about π.

When you verbally ask a kid what "pi(e)" is, they will almost certainly tell you it's a dessert, and then proceed to share their favorite kinds of pie with you. Here's the coolest way to introduce π as 3.14 to kids in a way they will remember.

Write "PI.E" with a pointy "P" and a period between the "I" and the "E". Ask your kids what they read: "pie" should be the answer along with a lot of OCD kids saying that you wrote your "P" wrong and put the period in the wrong place. Be patient with those kids. I was one of those kids. :-)

Hold up a hand mirror to the right of "PIE." Suddenly, "PI.E" becomes "3.14"! Amazement should ensue. 

Do NOT write "PIE" with a rounded "P" or you will get "3.19" which defeats the purpose. Your students will remember what they see first, so if the first thing they associate with "pi(e)" is 3.19, they will struggle with changing that to 3.14.

If you're teaching an entire class this concept and can't get hand mirrors for all your kids, either trade off with the hand mirrors you have or bring in a big mirror and you can do this on the whiteboard or Smartboard and everyone can see! In my experience, kids remember best if they do it themselves, so individual mirrors would definitely be ideal.

Keep in mind that this does not teach your kids that 3.14 is symbolized by "π" or even that 3.14 is "pi" and not "pie." It teaches them aurally that 3.14 is "pi(e)". Have this activity be the attention grabber of your lesson before you continue with the π and explaining irrational numbers and all that.

In one of the captions above, I mentioned that your kids remember what they see first. So that means that they've now associated "p-i-e" with 3.14. This is a good time to introduce the symbol "π".

This is a worksheet/coloring sheet I made where the kiddos can write what kinds of "pie"
the icons represent under each image.

Have your students color the π symbols as if the symbols were the previous kinds of pie. Let them be as creative as they want! If some kid does brown on the apple one and doesn't put a leaf on top, ask why first before giving them no points. They may have been doing a lattice-top apple pie or apple pie filling--neither of which are red or have leaves. If some kid leaves the chocolate one white and then tells you it's a white chocolate pie, don't tell them they have to color it brown. Ask them if there's anything that goes with white chocolate that they could draw inside the symbol (eg. raspberries). If you challenge your smart-alecs to take it a step further, they will become your super-stars. 99% of the time, the reason they're smart-alecs is that they're smart and they're bored. Ask me how I know. :-)

It's fun, it's not complicated for your kids to complete, it's easy for you to grade, and they will start associating the symbol π with "pie." You've shown them "pi" on their worksheet, but you haven't drawn attention to it.

After they're done coloring, put a π symbol on the board and ask them what symbol it is. "Pi(e)" will be the verbal answer. Then ask them how it's spelled. You're going to have one or two kids who actually read the title of the worksheet. Let them be thrilled that they know how to spell it! Write it on the board and ask your students, "Do you like p-i-e more or p-i more?"

Note: If some kid says "p-i" you've got a brown-noser. :-) Just kidding! Don't give them attention for it, though, if they do say, "p-i". The only reason they're saying that when they don't even have a firm grasp on what π is, is to get attention.

Back to the lesson: "Do you like p-i-e more or p-i more?"
"P-I-E!!!"
"So would which one would you want more of, p-i-e or p-i?"
"P-I-E!!!"
"Does p-i-e or p-i have more letters?"
"P-I-E!!!"
"So how do you spell this symbol?" Point to symbol on board.
"P-I!!!"
"How do you spell it?"
"P-I!!!"
"How is this symbol spelled?"
"P-I!!!"

It works out pretty well. Now, if you're introducing π to your class, you've almost certainly introduced the "approximately equals" sign: ≈. So at this point, go ahead and write, "π ≈ " on the board. Ask the class if they remember (from the mirror activity) what number should go there. This is a stretch because your kids have not seen this setup. You should have a couple of kids who remember, though! 

At this point, you can leave it at that and eat your pie (if this is a young class and you're simply celebrating Pi Day), or you can eat your pie while you go on to explain irrational numbers, circumference, or anything else you're planning on talking about that lesson. 

Don't forget to have your pi digit recitation! In elementary school it's very typical for kids to memorize 50 digits for extra credit. Make sure you give your kids a paper of the first 1000 or so digits at least a week before so they know about it and can prepare. And give every kid that memorizes the amount of digits you've set as the minimum extra credit, not just the kid who memorizes the most digits. In high school, it's not typical for kids to memorize any, because by that point in their lives, they have "cooler" things to do. Still, if you make it a competition at the middle and high school levels, you'll get a few bites. Make a trophy, keep tabs on who is the reigning champion of π, do anything you can to make it a thing.

I hope this has helped and gives you all some cool ideas! Do spinoffs, use my stuff, make it better! Make your goal to help kids have fun with numbers! Happy Pi Day! :-)

"Be the change you wish to see in the world." --Gandhi