Tuesday, March 25, 2014

Common Core Math


The "Old fashioned" way.

  32
-12
----
20

The new "Common Core Math"

32-12= ____

12+3=15
15+5+20
20+10+30
30+2+32

 Now you add the second number in each row to get the answer...3+5+10+2= 20

Here's an explanation someone told me on FB...

"Here's what they're doing: Take the second number (12) and add up to the next multiple of 5/10 (+3). Then take that answer and add up to the next multiple of 10. Do that till you get to 30 and then add up to the first number (32). Then add that column of numbers you used to add up to those multiples, and that's your answer. ...

What stuns me is that anyone thinks this is better or easier. The ONLY thing I can think of is that this way involves all adding and no actual subtracting. So, you're never really teaching subtraction at all here -- just using adding to get around it. HOW is that a better skill?

Does this make sense to anyone? They have over complicated what used to be a simple process and kids don't even get it. Oh and if they need help at home, well they are kinda shit outta luck because most parents don't have a clue as to how to figure this out.