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Doing Mental Math vs Speed Math

In recent years, there has been a lot of changes in the way math is taught in school.  Many current parents in Mississauga grew up learning math by memorizing the multiplication table and doing speed math.  We learned to do addition, subtraction, multiplication, and division by heart, use flash cards, do math sprints and repetitively used math worksheets so that we can immediately provide an answer to a math question, e.g. 5 + 8 = 13.

While we are not claiming that this is a wrong way to teach math, there are other ways that math can be learned. Instead of doing speed math where some students may develop anxiety due to the timed tests, here at Mathnasium, we focus on doing mental math.  We believe mental math is better because it gives you the skill to figure out math questions even if you have not memorized the facts.  It teaches you how to not use fingers to do calculations but break apart numbers and construct your answer.

To give you a better idea of how we teach math, here are three example mental math techniques we use at Mathnasium of Lakeview/Mississauga using the Mathnasium Method™:

Example 1: Doing Division using Mental Math

Math Problem: Divide 75 by 6

Mental Math Approach: 6 is the same as 2 x 3, so instead of dividing by 6, we can divide 75 by 3 and then divide that quotient by 2. So, 75 ÷ 3 = 25, and 25 ÷ 2 = 12 1/2. Done!!!


Example 2: Find the Perimeter of Shape

Math Problem: Find the perimeter of the shape below using the information provided


Mental Math Approach:  The length on the bottom of the rectangle is the same as the length on the top, although the top has been split into two pieces. Similarly the width on the left is 11 inches and the width on right is also 11 inches, again in two pieces. Given the length of the side is given in inches and the length of the bottom is given in feet, let’s change 2 feet into 24 inches (2 x 12).

With that, 11 in + 11 in + 24 in + 24 in = 70 inches.

Note that it is not necessary to know the exact measurement of the length and width. All that matters is that we know the total length of each.


Example 3: Finding 100% of a Number

Math Problem: A man spend $10, which was 20% of his money. How much money did he have to start?

Mental Math Approach:  If 20% of his money is $10.00, then 40% is $20.00. (20% + 20% = 40%). Similarly, 60% is $30.00 (40% + 20% = 60%), 80% is $40.00, so 100% is $50.00 – the amount of money the man had to start.

And an even faster way to approach this problem. There are 5 20%s in 100%, so this problem calls for five sets of $10.00, which equals $50.00.


Bonus: Click here to see a video of a 6 year-old doing mental math in action


Learn more about how mental math helps your child

Find out more about the various ways we help your child understand math and take the anxiety out of learning math. Contact us today for a free math session for your child and see if we are a good fit for your child’s needs.

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About the author
Erena Shkodra
Erena Shkodra
With more than fifteen years experience as a teacher, primarily an elementary teacher of grades 1 to 6, Erena excels at helping students who struggle with math. She has a Bachelor of Education diploma (OCT), Intermediate Math qualifications, Montessori Elementary Teacher certification, and a B.A. with a major in English Literature and Grammar. Following her Orton-Gillingham teacher training, she mentored and tutored students with Dyslexia and ADHD, to not simply catch up but to exceed expectations.