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.