How to get DS to understand 80+3 is not eleventy...

[ShowerOfMonsters]

Tearing my hair out here!
YouTube recommendations
Non internet requiring apps
Anything.

Arrow cards where the 80 is show. Then you put the units over the zero?

It is the place value part he isn’t understanding rather than the adding. Google ‘arrow card place value interactive games’ and there should be something useful.

You can't argue with that sort of logic!

A number line or number square then literally count on.

If you don't have those, what about a tape measure? He'll be able to see that the answer is 83

How old is he?

I used pennies and coins to teach my son maths, he found multiplication much easier to grasp.

How old is he and why are you teaching him?

If he's too young for school then no need to get him to understand it imo. If he's 14 I'd say you need some specialist help

How old is he?

80+3 is a bit of a random sum, what’s the context here. Is he able to do other addition?

Well start with eleventy isn’t a number and go from there?

can you get hold of deins and show him or something else concrete
like lego

I can see his logic! He needs to learn which column to put hundreds, tens and units in to get this or any sum right. My DS had a blind spot for this too.

I think 'eleventy' is absolutely delightful, never heard that before. I will definitely use it! Don't really get the relationship to 80+3 - but expect he does.

No apps needed, a number line is literally the easiest visual way to explain this. Put a sticky dot under 80 count on 3 and put another sticky dot, repeat with different numbers until he understands the concept.

Do you mean 80+30?

I think 'eleventy' is absolutely delightful, never heard that before

I complain quite frequently that I have "eleventy billion" emails in my inbox. Not that I'm over dramatic or anything

No, I mean 80+3

He had a column of sums
60+1=
70+2=
80+3=

He's 8 (nearly 9) and very, very aware of his inability to understand maths. School are being pretty shit at helping him, so it falls to us.

I've been using a number line (square) with him for 3 years...

I don't know about the adding. I had to spell (!) out the first two. 90+4 he said was 98

Use an abacus.

Dienes or numicon- visuals help.
Or bunches of straws in tens and ones.

Does he understand 20+3=23? If not, you probably need to tackle this first and work up towards larger numbers!

You could also visually represent the tens and units with coloured in squares, so 8 rows of 10 coloured in blue, plus 3 single squares coloured in red. Again, start small and work up! If he can't do 20+3, he won't be able to do 80+3.

If he cannot add 60+1 and 70+2 then I would honestly recommend a tutor. If he is lacking confidence then this will work towards solving both issues, the maths difficulty and the lack of confidence.

I would also be discussing with the school what strategies they are putting in place it's not good enough for them to shrug their shoulders.

Do you mean 80+30?

I assume he knows that 8+3=11 so he thinks that 80+3="eleventy"

Do you have concrete materials such as diennes?

If not, then online interactives such as this one may be helpful.

Lay out the tens for e.g. 60. Then add one unit for the +1. On a board divided into different place value columns, write the 6 (in the tens column) and then the 1 (in the units / ones column)

Then repeat a lot! It sounds to me as if he is not understanding that the 80 is made up of 8 tens, and the 3 is made up of 3 units - and things like coins don't help as a 10p does not look like 10 1ps.

If the adding on is too hard, just get him to make lots of numbers - first multiples of 1 (4,5,9), then multiples of 10 (40,50,90), then combinations of those (41).

Take the numbers like 41 apart and show that they are, quite literally, 40 + 1, so that you can do that process the other way round (put 40+1 together to make 41).

Each step may take a long time. Don't move on until he can do each step really confidently.

If he struggles even with numbers within 10 (so might find e.g. what 7+2 is hard) then Numicon is probably the appropriate visual manipulative, and comes with excellent step by step plans. Your school should have it, as it is really expensive to buy privately.

I would also say that you should be booking an appointment with the SENCo, and discussing the need for further investigation and rigorous support / catch up programmes to be implemented with him daily.

I taught a child with dyscalculia some time back, and actually they really improved when we moved on from mental strategies to 'pencil and paper' methods, because the standard algorithms for e.g. column addition only require the addition of a few small numbers. however, they did also have 3x weekly Numicon 1:1 sessions to 'back fill' their understanding, as using the standard calculation methods was at best a rote learned process.

Thinking about it, try setting out the calculation in the classical vertical form, and adding first the units then the tens. It demonstrates the place value much more clearly than the calculation laid out horizontally, and may give him a 'way of getting the right answer' and more confidence, behind which you can start to build understanding.

We have cuisenaire rods.
I made him this chart to go on his wall and go through it with him a couple of times a week.
SENCO won't use dyscalculia aids without a diagnosis. The won't assess him til next academic year.
School muttered when I said I'd shown him the old-fashioned column method to add.
My logic was at least he can use his 0-20 number line.

It’s tens and units, just like the others.