What Was Wrong With the Old Way?

Photo courtesy of Americans Against Common Core.  Used w/ permission.

The "standard algorithm" shown at the bottom of the picture works every time if one knows the basic math facts.  So why aren't schools teaching that, and having children practice problem after problem this way a good majority of the time?

I understand that sometimes we want to give children "number sense" or show them different ways to solve a problem. There's nothing wrong with occasionally showing children this sort of thinking once they have a solid understanding of how to do it the standard way.  Certainly what I often would do in cases like these is take the 200 away right off.  I'm left with 368 - 93, which I would either line up old-school style and solve OR I'd take 100 away and add seven.  Whatever I felt was easiest at the time.

But I think if I were shown this backward/ shortcut way of solving the problem at the same time I were learning my standard algorithms, I'd be very confused.  And that's just what many schools are doing now.  I know that works for some people, but I don't think we're helping a large number of children with this teaching method.

Worse still, schoolchildren often bring home entire packets of homework which must be done as above and/or the answer "explained" in a sentence.   Often schools hold entire "how to do Common Core math" parent nights to explain to the parents how to help their children with schoolwork at home.

It just seems like a lot of energy to expend on something that will be understood more naturally later.

Caveat:  this sort of convoluted math has been in schools since Patrick was little, and he'll be 23 this year.  So the example above is not just a "Common Core" math problem, but a problem we should all have with the "new math" that is de rigueur in all schools under the current system.  Still... yuck.