My almost 8 yo DS catches onto math very quickly except for the following problems. They seem just like common sense to me, so I can't figure out how to get him to understand. I also don't understand why he doesn't get it when everything else math wise has co me so quickly to him. We use Horizon math, if that matters. Problem example: 79= ___________ + _________ Answer: 79= 70 + 9 We even have to do three or four problems before he catches on and we have done them several times and he still has problems each time. Help please!
Do all of the questions have the same type of answer? Like 80+something, or 40+something, etc? Like, is 70 + 9 the only correct answer to that question, or would 78 + 1 also be considered correct?
ok. I asked because my 8yo gets overwhelmed if there are too many correct answers. He gets flustered over having to pick just one answer. In your case, I'd probably bring it back to basics, so he can grasp that the question is asking him to break the number down into tens and ones. Break out the base 10 blocks so he can visualize it.
As Angie says, it's an understanding of tens and ones. Base Ten Blocks would work. If you don't have any, get little soufflé cups or the mini muffin cups, and put ten counters in each one.
Can you just explain start with the number in the ones column and write that down, now look at the tens column and write that number (reminding him that it represents groups of 10). That is how I did it with dd. You might need to do as Angie said and do something more visual or hands on.
I think you should take a little break and go back to place value. It's super important that he understands it. You can find some good videos on youtube.
Visual aids might help a lot. The exercise is meant to reinforce an understanding of tens and ones. Before long, they'll also introduce hundreds and thousands...so getting a firm grasp of this one is important now. Get some little objects...pennies could work. Have him count some of them into piles of ten. Have him tape them with some masking tape and write "10" on them. Then leave some pennies single and tape "1" on them Now give him a two digit number on card to look at. 46. Show me how many tens you need to use to make this number? How many ones do you need to use? Let him visualize those four taped bundles and the six singles. He'll get it. After lots of practice and success....show him ten "10" bundles taped together with "100" on it. Then ask him to show you how to make 146. when he lines all the bundles up....show him how the bundles coincide with the numbers on the card. Good luck!