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Magically Squaring Numbers

My college math students lack confidence (I classify them as mathphobics.); so, I like to show them math "tricks" which they can use to impress their peers.  I encourage them to know their squares through 25. (Yes, I know they can use a calculator, but the mind is so much quicker!)  When we get to solving equations using the Pythagorean Theorem, I introduce this trick. Please note: For the trick to work, it must be a two digit number that ends in 5.
Suppose we have 352.  (This means will be making a square.)
  • First, look at the number in the hundred’s place. In this case, it is the “3”. 
  •  Next think of the number that comes directly after 3. That would be “4”. 
  •  Now, in your head, multiply 3 × 4. The answer is 12. 
  • Finally, multiply 5 × 5 which is 25. 
  •  Place 12 in front of 25 to get the answer. Thirty-five squared is 1,255.
  • 3 × 4 = 12      5 × 5 = 25       
  • The answer is 1,225.
This means that we can build a square that is 35 by 35, and it will contain 1,225 squares or have an area of 1225 squares.

Now let's try 652
  • One more than 6 is 7; so, 6 x 7 is 42. 
  • Place 42 in front of 25 (5 x 5) and so 65 squared is 4,225.
  • 6 × 7 = 42      5 × 5 = 25      
  • The answer is 4,225.
How about finding the square root? We begin by looking at the numbers in the thousands and hundreds place. In the answer of 1,225, we would use the 12. Think of the factors of 12 that are consecutive numbers. In this case, they would be 3 and 4. Use the smaller of the two which, in this case, is 3. Now place a five after it. You now know the square root of 1,225 is 35.
Thirty-five represents the length of one of the sides of a square that contains 1,225 squares.

Now, try some numbers on your own. When you get comfortable with the "trick", try it with your students. They will find out that math can be magical!

Why is 'x' Usually the Unknown in Algebra?

Ted Talk
Again, it's time for some math information you might have missed in school. (Don't worry, I missed a great deal as well.)  Today's question is: Why is the letter "x" the symbol usually used for an unknown?

Even though the letter "x" is commonly used in mathematics, its use often appears in non-numerical areas within different industries such as The X Files or Project X. Terry Moore clears up this mathematical mystery in a TED Talk presentation at Long Beach, California.  In a short and funny four minute talk, he gives an unexpected answer to "why." Just click under the illustration to find out the reason!

A Go Figure Debut for a Floridian Who Is New!


Her TPT Store
Today my blog highlights Kelly Ann who is an elementary teacher from Florida. She started out teaching first grade, but after four years, she “graduated” to fifth which is still her grade level.

Regardless of the present-day hardships most teachers face, Kelly Ann loves her job. Even at a high-socioeconomic school like hers, her fifth graders come to school with a lot of baggage. Not only is she teaching content that they need for real life, but she enjoys helping them learn how to be good human-beings. Because her students spend such a large part of their day with her, she desires to be a caring, loving, authentic role model for them. That is why she describes her classroom as a family environment. She wants her students to take care of each other while they learn as well as to use their strengths to support each other.

Kelly Ann married her high-school sweetheart. (How romantic!) They have two small children - a four year old and a four month old; so, she is quite a busy lady! Generally, her life with a new baby consists of trying to keep everything afloat and trying to do Teachers Pay Teachers whenever she can! In other words, her free time is null and void. Fortunately, she is able to take this next school year off to be with her kiddos thanks to TPT.

Her Teachers Pay Teachers store is called “Created by Kelly Ann.” Right now it contains 101 quality and reasonably priced resources that are generally focused on intermediate science and social studies, with some ELA and test prep items mixed in.

One of her bundles that my husband is interested in (he teaches 8th grade science) is her Variables in Experiments Bundle. (We all love bundles because they save us $$$.) This resource includes three activities to help students practice and review independent and dependent variables, a difficult concept to master. One of her buyers left the following comment about this resource:

“The scavenger hunt was a huge hit in my class. I was also easily able to see the students who needed some additional help.”

Free Item
Out of the five free resources in her store, I found this one to be well received. It is called Teaching Test-Taking Strategies Posters. These are test-taking strategies posters that her students practice all year long to help them prepare for the inescapable standardized testing. As I looked at the 91 ratings for this item, I discovered that buyers thought these posters were not only useful but just what they needed.

She just launched her new website that incorporates her blog within it. It is entitled Created by Kelly Ann as well. Recently, she has started to create "Quick Tips for Teacher-Authors" that can also be found on this site, Instagram, Facebook in addition to Pinterest.

In everything Kelly Ann does, her teaching, creating her resources, her blog, etc., she has set high expectations for herself!  Check out her store as I know you will love what she has to offer! My husband did, and he is now a Kelly Ann “fan!”