The new New Math: Byzantine subtraction in Common Core « Hot Air: "I’m pretty good with patterns, so I see what the intent is with this method. It’s to build the answer through a series of additions, taking four steps on paper plus a number of cognitive judgments along the way. What I can’t see is why anyone would ever need to use this method to actually subtract one number from another. In the old New Math, breaking equations down into components based on the places in the numbers could boost understanding of algebra and help one learn to do more complex equations in the head. That’s clearly not the case here — the “counting-up method” requires a paper calculation and more complicated cognitive judgments than simply subtracting and carrying over. Furthermore, as one of Erick’s commenters noted, even if one argues that it prepares children for higher math functions, how do you deal with negative numbers using this method?
As Erick concludes, the only possible value in putting this in a textbook is just that it’s new. I’m all for new when new improves on old, but … this is sheer nonsense."
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