In which year is column subtraction (with carrying) of 3+ digits normally taught?

[Iamnotminterested]

Thankyou in anticipation!

It's not taught like that at state primary school. Chunking is the norm in my experience.

In Y5, but may vary according to the child's ability.

It's not carrying though - that's for addition. In subtraction it is decomposition.

crazygracieuk Remind me again what chunking is .

Why isn't is taught by column method? Is chunking considered easier?

WTF is decomposition, bigTillyMint?

dd did it in P4 (scotland equivalent to Y3 I think). They do column addition and subtraction.

p.s. she uses the 'decomposition method' although when I was at school we used the 'equals addition method' www.mathsteacher.com.au/year7/ch01_whole/03_sub/sub.htm

My ds has just started doing this in Year 3 (he is 8).

Mintyy Do you mind me asking how able your DS is at maths?

Some schools are rebelling and going back to column methods for most DC, I think, crazygracie and ditching stupid overcomplicated "recipes", Thank God...

DS did it first in Y3, I think - continues to consolidate and expand it in Y5 but they are doing long division and column multiplication (by nice old fashioned methods) as well. DS "taught" DD (YR) to do column addition and subtraction the other day - I am not saying that she could do it unaided at all whatsoever, but she could do the "little sums" and she absolutely got that by doing the little sums in the right way she was doing the "big sum".

He is on the "top" table (so top 5 or 6 out of a class of 30) but not any sort of child genius .

Dd2 has done this in year 3-that's top set though.

Y3 DS is doing this using a number line and complementary addition.
So if he had 536-284 he would do
284 (+16) -> 300 (+200) -> 500 (+36) -> 536
Answer = 16+200+36 = 252

I know that's not column subtraction, but does it have a name?

DS is in year 5 and he uses this method. Don't know when he was actually taught it though.

So would I be correct in thinking from all the helpful replies that it would be taught from year 3 up for more able children?

Mine's doing it in Year 3 too, also top set but not a genius by any means. This morning he told me that 3x6 was 15...

DS is doing it in yr 3. He's top set.

Year 3 top set, Year 4 mostly.

Another top set, year 3.

We teach column addition by partitioning in year 4, although I have taught it to my top groups of year 3 because they are a particularly able cohort.

...134

• 345 ----- ...400 .....90 .......9 ---- ...499

but don't teach 'carrying' until year 5 or 6.

I am all for number lines and not carrying. I know 'carrying the ten' is how most parents understand it, but I think it overly confuses things and doesn't teach a good understanding of relative number.

or 479!

oh god, my brain has turned to mush

stealthsquiggle, that's interesting. FWIW I think that for many children, the NC spends way too long on other methods when they have grasped the concept and just could use the quickest method.

Seona, I was taught the equals addition method and my brain still tries to return to it even after 25 years of teaching the decomposition method

Tilly - I am not sure how much freedom schools are now being allowed, TBH, or how much they are "taking". My DC are at an independent school, and I talked to the head of maths the other day - his opinion was that some of these methods are a good last resort, for DC who really, truly do not understand, but that until age 12/13 the emphasis should be on trying every which way to get them to get the underlying concepts before resorting to teaching "recipe" approaches. The school dallied with chunking type methods in Y2 but when they realised that DS was getting frustrated at having to go all round the houses to arrive at an answer which he could get very straightforwardly, they backed off (for his group, at least - I have no idea if they still use those methods with other sets)

DS is in year 3 and does column addition and subtraction. He uses chunking for division. He has asked me to show him how to do ling multiplication (he uses the grid method at school I think). He is on the top table and is pretty competent at maths.

Miranda - DS showed me the grid method the other day - as he had encountered it for the first time and really didn't like it. I can see that it works, but seems to have more calculations (and therefore more room for error) than the method which I learned, which is how DS normally does it, and whose name I don't know .