mental maths and numberlines
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mental maths and numberlines
Hello,
Can someone tell me if, when adding, say, 56+38, it is best to learn to do lots of this sort of question with number lines first, so that you can mentally picture the numberline at some point and do these sums mentally? My year 3 DS seems to be imagining the numberline in this way: 56 + 30 and getting to 86 quickly but then has to practically count on his fingers to add the remaining units, instead of being able to mentally bridge the 10 on a numberline and so on.
Hope that made sense . I just wondered if doing lots of these sums with a numberline would help him to finally get it mentally, or whether there was a more efficient method.
Thank you!
Can someone tell me if, when adding, say, 56+38, it is best to learn to do lots of this sort of question with number lines first, so that you can mentally picture the numberline at some point and do these sums mentally? My year 3 DS seems to be imagining the numberline in this way: 56 + 30 and getting to 86 quickly but then has to practically count on his fingers to add the remaining units, instead of being able to mentally bridge the 10 on a numberline and so on.
Hope that made sense . I just wondered if doing lots of these sums with a numberline would help him to finally get it mentally, or whether there was a more efficient method.
Thank you!
Seize the day ... before it seizes you.
Re: mental maths and numberlines
Yes - number lines are a good support -
I'd encourage him to tackle 56 + 38 by one of
* 56 + 30 = 86 then + 4 to get 90 then add the remaining 4 (this avoids bridging the ten)
* adding on 40 and subtracting 2 - it's quicker!
I'd encourage him to tackle 56 + 38 by one of
* 56 + 30 = 86 then + 4 to get 90 then add the remaining 4 (this avoids bridging the ten)
* adding on 40 and subtracting 2 - it's quicker!
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- Posts: 1411
- Joined: Mon Mar 08, 2010 2:03 pm
Re: mental maths and numberlines
Thanks so much Guest55. I thought adding units to the nearest 10, in this case 90 and then adding on til you've added all the remaining units, was called 'bridging through 10'!
and, yes, I can see that adding 40 and subtracting 2 is far better - much quicker. Thank you!
and, yes, I can see that adding 40 and subtracting 2 is far better - much quicker. Thank you!
Seize the day ... before it seizes you.
Re: mental maths and numberlines
You can call it bridging through 10 ...
http://ictgames.com/bridgingThro.htm" onclick="window.open(this.href);return false; has some games about it ...
http://ictgames.com/bridgingThro.htm" onclick="window.open(this.href);return false; has some games about it ...
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- Posts: 1411
- Joined: Mon Mar 08, 2010 2:03 pm
Re: mental maths and numberlines
They look great games. Thank you very much!
Seize the day ... before it seizes you.
Re: mental maths and numberlines
I've used the catapult one with y5/y6 children who found it hard to visualise and it was very usefulGuest55 wrote:You can call it bridging through 10 ...
http://ictgames.com/bridgingThro.htm" onclick="window.open(this.href);return false; has some games about it ...
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- Posts: 1411
- Joined: Mon Mar 08, 2010 2:03 pm
Re: mental maths and numberlines
Thanks for the pointer, Yoyo
Seize the day ... before it seizes you.