Mathematics for Teaching Category: Number Sense

Category: Number Sense

Free Fractions Pamphlet

I just want to promote in this post James Tanton’s latest pamphlet on fractions. It’s FREE for download. Just click Pamphlet on Fractions. Tanton writes: If fractions are pieces of pie, then what does the multiplication of fractions mean? (You can’t multiply pie!) If fractions are proportions, then what are their units? Amount of pie per…

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Why PEMDAS is ‘morally’ wrong

Here’s a video that explains why you need to memorise PEMDAS (or BODMAS, BIDMAS, depending where you are in the world) order of operation and why you don’t need to. Minute Physics who made this video made a mistake in assuming that PEMDAS is taught in schools without emphasising that multiplication and division should be…

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Why do we ‘invert’ the divisor in division of fractions

The easiest (and the most common) way to teach division of fractions is to just give the rule: To divide 5/8 by 2/3, just multiply 5/8 by the reciprocal of the divisor, 2/3. That is, 5/8 ÷ 2/3 = 5/8 × 3/2 = 5×3/8×2 = 15/16. If this is all we want our students to learn why…

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911 math assistance service

A four-year old calling 911 for math assistance. History tells us that zero was invented much later than most of the numbers. It was not even accepted as a number right away. Why should we expect a four-year old to think of it then? And take-aways without context for them? Anyway, this video is cute….

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The many faces of multiplication

The following table is not meant to be a complete list of ideas about the concept of multiplication. It is not meant to be definitive but it does include the basic concepts about multiplication for middle school learners. The inclusion of the last two columns about the definition of a prime number and whether or…

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