How important are number lines

[Strawberryorangejuice]

My year 4 does not get number line for subtraction, no matter how hard he tries. How important are they? He can subtract using column addition and partitioning. He is becoming disheartened. He believes he ovetheard the TA say to the teacher that he's trying hard but just can't do it yesterday. Whether or not he did and whether or not it's about him, I do not know but he's feeling very down about number lines at the moment as a result and is convinced everyone thinks he's stupid. It doesn't make much sense to me either so I'm not really able to help in a way that doesn't confuse!

Plenty of resources online and YouTube videos you could watch together. You could make or print a number line.
You could speak to the teacher for advice too. Things move on quickly and if he didn’t get the concept he will need some support.
Just remind him it’s OK to say when he doesn’t understand something and doesn’t mean that he’s “stupid”

At least one of my three never understood how to use number lines. They’re now well into secondary school and it’s doesn’t seemed to have mattered one jot! They’re way maths is weight now (at least it was at my kids primary) was that they’d teach several different methods (number lines, partition, column, arrays etc) to solve the same problem. The idea being as they moved up the school and were presented with more complex problems they had a “toolbox” of methods they could draw upon (choosing the tool/method they found easiest to use) to solve it. Because no child learns in exactly the same way. Having a toolbox ensures each child stands a greater chance of solving the problem. So if you DC understands other methods perfectly well then I wouldn’t worry too much.

I was a primary school teacher. I think number lines are not always intuitive for children to pick up for subtraction and addition. How your son thinks about himself and maths is really important as it would be unhelpful for him to start feeling under confident or anxious about maths as this would likely inhibit his learning. It’s also really important that he holds on to the idea that maths is supposed to make sense.

if it was me a would get out/buy a tape measure or two and measure things with him. This is a number line we use. Talk about if we wanted to make it 10cm shorter how long would it be, and jump your fingers back ten hops/cm, same for eg 15cm more. Maybe measure other people in the family and work out the difference using the tape measure as a number lines. Or find the biggest table, how far you can both jump from standing, hop from standing, anything you can measure and then calculate how much more he can jump than you etc. maybe you and he can think of fun things to compare. Also maybe then do slightly more abstract school style number line problems and help him apply his experience with the tape measure to these, good luck.

I don’t know what a number line is and I’m doing great!!

I also agree with pp that some children find number lines helpful and some don’t. But if it’s bothering him and school are giving importance to it then it might be worth helping him understand them more.

Number lines are just a stepping stone between basic counting and proper addition and subtraction sums.

They aren't, in themselves, important. In fact they are never touched upon again once they move on to column subtracting and addition.

So don't worry.

Equally, find the relevant White Rose maths work book and watch the videos and do the work book together. It should click after that.

But still, don't worry he's doing great.

Paving slabs, chalk and lots of jumping using the appropriate language. Physical use is great.

However, if he has the concept of addition and subtraction a number line is just another tool to develop understanding.

Thank you. This is reassuring. I'm happy to help him learn it but it is causing him so much stress that if I can reassure him that if it isn't his strength then the other ways will suffice then I would like to do that too!

Number lines are also present on rulers....often the only tool permitted in a maths exam. Useful.

Thank you. He seems to get the smaller figures and can do that. But it's when we get in to say 9991 - 4017 (for example). He can't grasp the concept of doing it with larger numbers.

I so don't want his confidence to be knocked totally and I think it's great that he can do column addition and subtraction for those large numbers. I wasn't sure if not being able to do it confidently with bigger numbers further down the line may cause us issues.

What's the problem that he's having? Is it taking away negative numbers or which way to move that's more than/less than?

The axes on graphs are also sort of number lines so can he understand those?

I've spoken to his teacher earlier this week as at parents evening. The focus was very much on times tables and we weren't aware there were any specific struggles with number lines. It only came up today when my son brought up what he believes he heard the TA and teacher say and how that made him feel. As it's half term here (inset today) I can't speak to the teacher again right now.

Using a number line for big numbers seems... an unusual way to do it tbh. I guess it's the same as small numbers, but you're not going to "count along" 4017 steps so are they pretty much asking to do the subtraction in your head or by jumping in thousands, hundreds, tens and ones? Not sure of the technique there.

He seems fine on smaller numbers but not the larger ones in the thousands. I met with his teacher at the start of term and I said I was concerned that he seemed to not understand the concepts enough to apply them to larger numbers. This was in relation to something different, not number lines, but she didn't seem worried. It was probably week two of term though so early days. I feel it's the same here. Give him a number line in the hundreds and he can probably get it but not in the thousands.

Maths isn't my strong point but it is my husband's so he will work on it with him the holiday, I may confuse him!

So my husband looked at it on the Knowledge organiser and you seemed to work it out by taking it to the nearest thousand, hundred, etc...which gave you the answer. I can guarantee I'm not explaining this well but it made sense when my husband did!

I advised my son last week to use column addition for his homework of adding numbers but realise now he was supposed to do a number line for it based on what they had learnt that week. It made no sense to me as column addition seemed the best method and my son used that and got it all right. I don't think he would have with a number line.

Just to clarify, are we talking about using a blank number line as a strategy for addition and subtraction calculations or just counting forwards and backwards on a labelled number line in order to add and subtract?

I really appreciate the advice. Thank you. I've replied to a few comments but now have another child running a temperature so apologies if I've not replied.

Cross-posted!

He says they are given a blank number line then must write in the numbers in the sum and work out the answer.

In old-fashioned terms, we’d call it ‘shopkeeper method’ where you would count on to find the difference.
It’s a good strategy for children to use in a calculation like 20,000 - 13,458. When using column subtraction in a calculation like this, children often get confused exchanging across all the zeros.
The number line method allows them to jump up in increments and then add the values of the jumps together.
Some children don’t take to it, which is fine, but they need to make sure they’re really secure with column subtraction.

@Naanspiration wrote
*Number lines are just a stepping stone between basic counting and proper addition and subtraction sums.
They aren't, in themselves, important. In fact they are never touched upon again once they move on to column subtracting and addition.

Perhaps not in primary school, I don’t know. However, some teachers (me) use them in secondary school for some students. It’s a visual way of working with directed numbers, although I prefer a vertical line for that.

I second the toolkit idea. Hurray for @Pigsmightfly31’s post.

It also supports a mental strategy.
Lots of children default to column subtraction when a mental strategy would be more efficient. For example 2008 - 1997. By picturing or placing these numbers on a number line, they can see how close together they are…
1997 + 3 = 2000
2000 + 8 = 2008
3 + 8 = 11

Again though, if a child still prefers to use column subtraction, that’s absolutely fine.

Long division versus short division is another common concept where children seem to get one method but not the other and they always default to short division (even when it gets really complicated)!

He might find negative numbers harder to visualise when he comes to them when older, but other than that I can't see an advantage of using a number line. I always thought they were rather boring.

What I did do once with a child who was struggling with negative numbers on a number line was use stairs. So We found somewhere with two flights of stairs and put 0 in the middle then going up had 1, 2, 3 etc and going down had -1, -2, -3 etc.
The stepping up the stairs to count on and stepping down (backwards) to subtract really helped that child - but they did learn practically better than on paper.

Try an abacus. Seriously. I'm a TA who does a lot of numeracy interventions and they can work wonders for some children, using the physical rows as different place value columns can really help if the abstract notion of larger numbers is problematic.

Number lines are a good stepping stone.

They are also very good for visualising how you do mental maths.

Eg

1234-891

19 to get to 900
300 to get to 1200
And 34
19 and 34 is 20 and 33 so 53
Answer is 353.

Also extremely useful for visualising questions with negative numbers and also time questions.

With column methods you can get the right answer faster, but mastering number lines is worth it (and if he can't i would wonder what he isn't understanding). They are a useful tool in a mathematical toolbox.