August 20, 2021

Mélanie Boucarut

Mental maths for kids

I just learned about a method used to teach small kids how to do mental calculations that relies on “packages” of 10.

To add 7 and 8, you first complete 7 to reach 10, by plucking relevant units from 8 (i.e. 3).

Then you look at how much is left from the original 8 (8-3=5) and you add that to 10 (10+5).

So instead of doing 7+8, you’re really doing 10+5, which is much easier to solve.

Except that the way I was taught, and that I still use, is to find the easier operation, rather than the easier addition.

So for 7 and 8, I would multiply 7 by 2 and then add 1 to find the result (7x2+1).

My initial response, when I stumbled upon the “packages of 10” method, was to think that it is unnecessarily complicated.

It makes no sense.

Why go to so much effort when MY method is obviously superior?

Until I realized that the only real difference is that I’m very used to my method, so there’s a lot of mental ease in using it.

The new method requires me to slow down; a little – ok ok I’m not THAT challenged 😉. Enough at any rate to feel some friction, and thereby conclude that it’s not the right solution.

But… but… wait a minute… Isn’t that exactly the same as when I’m used to thinking a thought?

When something fails and I think “I don’t have what it takes” instead of going to “this specific trial didn’t work out; let’s find another way”, isn’t it simply because I’m very USED to thinking “I don’t have what it takes”?

Thinking a new thought creates friction. It slows us down.

Don’t make it mean that the new thought is incorrect or not applicable.

No bad horses, only untrained riders 🐴

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