Common Core Arithmetic – harder than it needs to be

The brave new world of Common Core educational standards has drawn much criticism, some of it justified.  Christine Rousselle, writing in TownHall, takes exception to the Common Core method of teaching addition and subtraction.  See her article here.

I will reproduce the examples Rousselle used to demonstrate the new “new math” and add my own comments.  Through these examples think of how you would solve the questions in your head, and then ask yourself if the Common Core method is a good way to teach basic arithmetic, or will it just confuse the kids?

Example 1 Subtraction: This one is fairly simple (correct answer is C)


I have to admit that this is the way I normally do it and so does my wife.

Example 2 Addition, it gets more complicated.


How did you add 26 + 17 in your head? Was it old school: Did you say 6 + 7 = 13, write down the 3, carry the one and add 1 + 2 + 1 = 4 to make 43?

I can understand what Common Core is trying to do, but their method seems awkward to me.

I would do it this way: 20+10 = 30, then 6 + 7 = 13, 30 + 13 = 43.

Here is another example from Rousselle’s article, a word problem:

“There were 54 apples set aside as a snack for 3 classes of students. The teachers divided up the apples and placed equal amounts on 9 separate trays. If each of the 3 classes received the same number of trays, how many apples did each class get?” (Answer is 18, 54 divided by 3.)

Rousselle complains that the second sentence is totally irrelevant, which it is, and would tend to confuse the kids.  That, too, may be true, but in real world problems one often gets irrelevant information.  What do you think?.

See also:

The dark side of Common Core Standards for education


  1. I’m glad I don’t understand the way it’s taught but can run the numbers in my head faster than most kids can punch into thier computer. 26+17 = 46-3=43

    1. Your method is quick and easy and can be applied to multiplication. No so for Common Core.

  2. I think learning math tables by rote(using flash cards, etc.) is the first step to learning to do math in your head. That worked well for me and for millions of other kids. Few schools, if any, teach math tables by rote anymore. While the Common Core method works, I’m not certain that students who do not have a natural aptitude for math will find it any easier, in fact, unless they use it repeatedly on a daily basis they just may not get it at all, given it’s a bit confusing at first. But, then again, doing math operations repeatedly whether it’s math tables or Common Core, is actually learning by rote in a way. IMO, if the old system wasn’t broke, why are they trying to fix it to begin with?

Comments are closed.