There's an article that's been kicking around the intertubes for the last couple of days. You'll find it here (as far as I can tell, this is the original version).
The gist is that there's an easy way to teach multiplication – that the Japanese have figured something out that we haven't in America. I presume that people are sharing because they wish they'd been taught that way in school.
To multiply 12 x 23, we draw these lines:
Now we count the intersections of the lines in each corner:
Here, we can add the two numbers in the middle column and put the numbers together to get 276, which is the correct result for 12 x 23.
But if we restructure the lines slightly:
And remove the lines:
We have exactly the same multiplication with the exact same calculations as we would have done had we simply done as taught in school.
Now to my objections.
The "proof" given that this gives the same result is only a demonstration that the result worked for a particular example. To prove that a method is correct, it's necessary to show that it will always work. If our students could actually demonstrate why these two methods always produce the same results, we'd be going somewhere.
I fail to see how this is any simpler. It actually takes longer to do. I suppose some students might object to the typical American method because it seems so arbitrary and they don't see why it would work, but the same applies just as easily to this visual method.
Try using bigger digits (not my own thought; I found this one online).
Most importantly, though, all of this misses the bigger point. It's not just about being able to perform computation. We have calculators for that. It's about understanding what a computation is, what it means, and how it works. This could be a useful teaching tool but could also be a crutch that prevents another generation of students from understanding one of the most fundamental operations in mathematics.
So why is this any different or better? Maybe I've missed something?
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