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Pi Day Is March 14th!

March 14 is Pi Day because March is the third month, and with 14 as the day, we get the first three digits of pi - 3.14! On Pi Day, nerds, geeks, and mildly interested geometry students alike come together and wear pi-themed clothing, read pi-themed books and watch pi-themed movies, all the while eating pi-themed pie. 

Pi is an irrational number that approximately equals 3.14. It is the number you get if you divide the circumference of any circle by its diameter, and it's the same for all circles, no matter their size. You can estimate pi for yourself by taking some circular things like the tops of jars or round plates and measuring their diameter and their circumference. Then divide the circumference by the diameter, You should get an answer something like 3.14. It should be the same every time (unless you measured wrong).  In other words, π is the number of times a circle’s diameter will fit around its circumference

Actually, 3.14 is only approximately equal to pi. That's because pi is an irrational number. That means that when you write pi as a decimal it goes on forever and ever, never ending. (It is infinite.) Also, no number pattern ever repeats itself.

Usually in math, we write pi with the Greek letter π, which is the letter "p" in Greek. You pronounce it "pie", like the pie you eat for dessert. It is called pi because π is the first letter of the Greek word "perimetros" or perimeter.  What is interesting is that in the Greek alphabet, π (piwas) is the sixteenth letter; likewise, in the English alphabet, the letter "p" is also the sixteenth letter.

But hold your horses!  The fascination with pi isn't restricted to just mathematicians and scientists. Pi has a special place in popular culture, thanks to its frequency in mathematical formulas and its mysterious nature.  Even T.V. shows, books, and movies can’t help but mention π.

For example, pi gets mentioned in a scene from Twilight, in which vampire-boy Robert Pattinson recites the square root of pi.  In an episode of the Simpsons, two young girls at a school for the gifted play patty-cake and say “Cross my heart and hope to die, here’s the digits that make pi, 3. 1415926535897932384…” 

Yep, whether you like it or not, pi is everywhere. Here are a few more places it has popped up:
  1. The main character in the award-winning novel (and 2012 film) Life of Pi nicknames himself after π
  2. A circular room in the Palais de la Découverte science museum in Paris is called the pi room. The room has 707 digits of pi inscribed on its wall. (The value of pi has now been calculated to more than two trillion digits.)
  3. In an episode of Star Trek: The Original Series, Spock commands an evil computer to compute π to the last digit which it cannot do because, as Spock explains, “The value of pi is a transcendental figure without resolution.”
  4. Pi is the secret code in Alfred Hitchcock’s Torn Curtain and in The Net starring Sandra Bullock.
Here is more arbitrary information related to pi that I found interesting.
  1. If you were to print one billion decimal values of pi in an ordinary font, it would stretch from New York City to Kansas (where I live). 
  2. 3.14 backwards looks like PIE. 
  3. "I prefer pi" is a palindrome. (read the same backwards as forwards)
  4. Albert Einstein was born on Pi Day (March 14) in 1879.
And let's finish this post with a couple of π jokes.

If you divide the circumference of the sun by its diameter, what will you have? Pi in the sky! 

What do you get if you divide the circumference of a jack-o'-lantern by its diameter? Pumpkin pi! 

On Pinterest, I have a board devoted to pi called "Life of Pi."  If you go there, you will find many cartoons, jokes and ideas to use for pi day. And to add to the fun, go to the website entitled “The Pi-Search Page” to find your birthday written with the digits of pi.

By the way, notice my "handle" of Scipi.  The Sci is for science (what my husband teaches) and the pi is for π because I teach math.

The Long and Short of It - Division

My remedial college math class is currently working on fractions. (Yes, even many college students don't understand them!) When we discussed how to change an improper fraction to a mixed numeral, long division came up. I showed the class a shortcut I was taught many years ago (approximately when the earth was cooling) and none, no not even one student, had seen it before. I wonder how many of you are unfamiliar with it as well? First let's look at long division and how most students are taught today. We will use 534 divided by 3.

Now if that doesn't make your head swim, I don't know what will. Everything written in the third column is what the student must mentally do to solve this problem. Then we wonder why students have trouble with this process. There is another way, and it is called short division for a reason. This is the way I learned it.......
I don't know about you, but I would rather have my students doing mental math to solve division problems than writing everything out in the long form. And the paper and frustration you will save will be astounding! So what will it be.....long division or short division?

Divisibility Rules Resource
As a Side Note: Since many students do not know their multiplication tables, reducing fractions is almost an impossible task. The divisibility rules, if learned and understood, can be an excellent math tool. This resource contains four easy to understand divisibility rules and includes the rules for 1, 5, and 10 as well as the digital root rules for 3, 6, and 9. A clarification of what digital root is and how to find it is explained. Also contained in the resource is a dividing check off list for use by the student. If you are interested, just click under the resource title page.

Dividing Fractions Using KFC

Ugh - It's time to teach the division of fractions. My experience has been that many students forget which fraction to flip and often, they forget to change the dreaded division sign to a multiplication sign. The other evening,  I was helping my 5th grade granddaughter with her homework. Really, she had completed it by herself, but she wanted me to check it. At the top of her paper were the letters "KFC". I asked her what they meant, and she replied, "Kentucky Fried Chicken." Now I have taught math for years and years, and I had never heard of that one!

She explained that the "K" stood for keep; "F" for flip, and "C" for change. Let's suppose the problem on the left was one of the problems on her homework paper.

First, she would Keep the first fraction. Next, she would Flip the second one, and then Change the division sign to a multiplication illustrated on the right. She would then cross cancel if possible (In this case it is).  Finally, she would multiply the numerator times the numerator and the denominator by the denominator to get the answer.
She was able to work all the division problems without any trouble by just remembering the letters KFC.

Yesterday, I was working in our college math lab when a student needed help. On the right is the problem he was having difficulty with. (For those of you who don't teach algebra or just plain hate it, I am sure this problem looks daunting and intimidating. Believe me, my student felt the same way!) 
First I had the student rewrite the problem with each fraction side by side with a division sign in between them like this.
Doesn't it look easier already? I then taught him KFC. You read that right! I did! (I figured if it worked for a 5th grader, it should work for him.) Surprisingly it made sense to him because he now had mnemonic device (an acronym) that he could easily recall. He rewrote the problem by Keeping the first fraction, Flipping the second, and Changing the division sign to a multiplication sign.
Now it was just a simple multiplication problem.  Had he been able to, he would have cross canceled, but in this case, he simply multiplied the numerator times the numerator and denominator by the denominator to get the answer.

So the next time you teach the division of fractions, or you come across a problem like the one above, don't panic!  Remember KFC, and try not to get hungry!

A Go Figure Debut for a "Retread" who is new!

Today’s Go Figure Debut is about Laura who didn’t become a teacher right away. She might be considered a "retread" since teaching is her second career.

Laura began working in the business world right out of high school and continued on that path for over eighteen years, getting married and raising a beautiful daughter along the way, while taking night classes as time allowed. She had an aptitude for numbers, and often found herself working in accounting positions. She stepped away from the corporate world to help a family member through a health crisis and began working on her bachelor’s degree while working part time. While on break from college, her daughter’s school experienced a flu outbreak among the staff, and they asked Laura to help out. She told them they were nuts; she was an accounting person, but, they were in a
bind so she agreed to help out.

Her first assignment was first grade. (I started there, too, and I can’t tell you why!) When her husband got home that night he asked her how it went. She revealed that she had the worst headache of her life, and she hurt in places she didn’t know existed. BUT it was the most awesome day of her life, and she couldn’t wait to go back the next day! Over the next three weeks, she filled in for almost every grade from kindergarten through 9th grade and even had a few days as the PE coach. A true passion for teaching was born. She has now been a teacher for over fourteen years, primarily in middle school mathematics.

Laura believes that students learn best when they are actively engaged with rigorous, high-quality, hands-on lessons that incorporate technology, group activities, offer differentiation, and reach across multiple subject areas to draw out students’ interests, passions and curiosity. She uses walk-abouts (see her paid resource), scavenger hunts, and learning stations to keep her kids moving and learning.

Laura has always shared her resources with colleagues and was surprised to hear over and over from them that she should open a store on Teachers Pay Teachers. She took that plunge three years ago. Laura is slowing growing her store as she continues working on improving herself and her classroom to provide her students with the best education possible. As most of us know, it is a never ending quest.

Laura currently has 119 products in her Teachers Pay Teachers store called Positively Pre- Algebra Plus. The vast majority are math related, with a few STEM and science resources. Laura’s featured paid resource is a Walk-About Bundle. This bundle includes twelve fun
Only $15.00
yet rigorous activities to help get your students out of their seats, walking around and engaged in math! They are excellent activities for students to work with a partner, in a small group, or individually to solve problems focused on similar skills.

Laura’s free resource is a cut-and-paste sampler activity.  This free sample pack includes cut and paste activities
Free Resource
for translating equations, one step inequalities, and percent of change. Cut and paste activities are a fantastic way to change up the routine for teens and tweens and to break free from worksheets. Laura’s cut and paste activities include multiple levels of difficulty to make differentiation easier for you while increasing student ownership in their learning. I was impressed with this resource as I could adapt the idea for the interactive journals my math college students do. She offers other cut and paste activities in her store that include: Scientific Notation, Distributive Property, One-Step Equations, Translating Equations, Percent of Change, Two-Step Equations, One-Step Inequalities, Simplifying Algebraic Expressions.

Take some time to visit Laura’s store and look at the unique resources she has created. I know you will find at least one that you love!