To not make DD correct her school work

[MayhapMayhem]

DS has dyscalculia and we have been spending the past few weeks trying to convince him that 43 = 34 etc

Teacher has returned some of DD's school work (Year below DS) and told her to do corrections. It's maths, her favourite subject and on the first page she has been marked 2/9. I haven't told her yet as she's going to be upset.

What has been marked wrong
47=28
34=12 (this has been corrected to 43=28)
63=18
16=6
45=20
27=14
36=18

In each case the teacher wanted the sum written the "other" way round I.e. 74, 61 etc.

On the next page
6+6=6*2=12 is marked as wrong.

AIBU to not make her "correct" it or should I tell her to write = b*a at the end of each sum?

"Nope 4 lots of 3 is 3 x 4"

Not if you write it as you say it!

But as pp has put, how was Op's daughter told to do it?

But if you have 3+3+3+3 & you are counting to know how many times to multiply,

Exactly, so you start with the number you have and know . 3 then times it with however many times you add it 4.

Princess are you a teacher?

Perhaps the teacher doesn't realise that 3 x 4 is the same as 4 x 3?

I’m sure the teacher does realise that. I think the problem is more likely to be whether or not you think it’s I portant to teach that 4 lots of 3 is the same as 3 lots of 4 but they have the same answer and you can use that to multiply mentally or whether you just tell children multiplication can be done in any order.

I think I agree with noble that I wouldn’t help her correct it unless you understand exactly what it was the teacher was trying to teach. It’ll lead to confusion.

diddl why?

X does not mean ‘lots of,’ it means ‘multiplied by’ so If it was 3+3+3 then I think it would be 3x2, as in ‘3 multiplied by 2’

If it wasn’t a number but was for example someone at a cafe ordering two identical meal they could say to the waiter ‘We’ll have a slice of cake multiplied by 3’ ++ and would receive three slices of cake. Saying ‘We’ll have 3 multiplied by cake’ does not make sense.

So the way your daughter has done it is correct, you put the number on each dice face first and then how many times that number has been multiplied by.

Sorry, I meant to type 3+3, obviously 3+3+3 would be 3x3 which is a rubbish example to use for this!!

Princess

Because you seem so sure that the teacher is wrong & I thought that perhaps you know how this should be taught.

*"X does not mean ‘lots of,’"

Well of course I know that it means multiply.

I also remember being taught that if you have four "lots of" three things & three "lots of" four things, they would be the same number of things, but "arranged" differently.

Yes, 3 lots of 4 things is arranged differently to 4 lots of 3 things. Equally 4 things in 3 lots is arranged differently to 3 things in 4 lots.

3x4 = 4x3 so actually it does not really matter which way you write it. To me the ‘four things multiplied 3 times = 4x3’ way makes sense but to other ‘3 lots of four = 3x4’ makes sense. The answer is 12 either way so how the calculation is written doesn’t matter for a simple multiplication. It would be ridiculous to tell a child that her working was wrong when quite clearly all of her answers were correct, it isn’t her fault that there are 2 correct answers but the teacher is only willing to accept the answer that matches her view.

Also just to add I am a trained primary teacher before anybody asks!

The teacher is correct. The dice show four groups of three.

This is how we teach it in Year 4 a)in preparation for the multiplication check and b) before moving on to division where the children need to grasp this before they can grasp the difference between a grouping or sharing division problem.

Yes, the calculations are commutative, but the teacher is correct that the representation with the dice is 4 groups of 3.

It might be the way that some schools/ teachers choose to teach it so that young children are able to grasp it, but that’s not because writing 4x3 as opposed to 3x4 is fundamentally wrong. Children should be taught that, unlike division/ subtraction, multiplication can be done in any order. This is helpful when, for example, multiplying 13x5/ 5x13 in your head as it is usually easier to count up in 5s than 13s.

The teacher marking this is wrong is the equivalent to a teacher marking a child wrong because they wrote 3+7= 10 instead of 7+3=10 because the teacher thinks the big number should always be first ready for teaching subtraction. It’s petty, it’s not mathematically correct and it’s not actually helpful when, if the child has got all of the answers write. the child has clearly understood multiplication.

Answers right*

I don't know if this helps but under the number you strategy we taught it as repeated x times.

So is repeated 3 times or x3

Like on a shopping list. x25 perhaps.

So 2+2+2 is 2x3.

But I noticed the new curriculum is v confusing and has seemingly moved away from that visual representation. I was taught this by a maths specialist as a part of an in-depth course the LEA ran.

I've banged my head against a brick wall at my own school over this.

But 4 groups of 3 can be represented as 4 x 3 or 3 x 4. I'm struggling to see why it has to be 4 x 3. It's definitely not 28 though...

Four groups of three is

Which is 3 x 4

For the PP who asked, not a teacher, I'm a TA. Don't know if that gives my "version" more credibility or less.

And three groups of 4 is

And yes 12...

And then you line those up as an array as above (button faces) and you see that it's commutable.

It only mattered as the favoured method of division was to introduce as repeated subtraction.

Yes that's right princess

As a pp says it's something to do with what operations actually do and mean.

I've got too many children interrupting to make head nor tail of what the teacher says though!

Numicon and dice work well but you have to understand what the picture means and that x means 'repeated'

I would say if they're all the same way it's probably fine.

If she'd written some as 'number of dice X number on face' and some as 'number on face X number of dice', I'd be more worried, because that shows she doesn't have a fixed method.

(I tutor for 11+/entrance exams if we're providing credentials! So mine are usually Year 3+.)

(As an aside, why bother having squared paper if you don't write in the squares! Looking at both DD and the teacher.)