Lesson video

Hello everyone.

Welcome back to another maths lesson with me, Mrs. Popel.

As always, I can't wait to learn lots of new things and hopefully have lots of fun.

So let's get started.

This lesson is called Explain how many 100s and 200s, 1000 is composed of, and it comes from the unit, column addition and subtraction with four digit numbers.

By the end of this lesson, you should be able to explain how many 100s and 200s 1000 is composed of.

Let's have a look at our keywords for this lesson.

Compose, counting in multiples, division and estimation.

Let's practise them.

My turn, compose, your turn.

my turn, counting in multiples.

Your turn, my turn, division, your turn.

My turn, estimation, your turn.

Fantastic, now let's have a look at what they mean.

When we think about what a number is composed of, we think about the parts that make up the whole.

Counting in multiples is also known as skip counting, when we count by a number other than one.

Equal divisions can be found on a number line or scale for equal values.

When we estimate, we find the value that is close enough to the right answer, usually with some thought or calculation involved.

So these keywords and definitions are really going to help us with our learning today.

So let's get started.

Let's have a look at our lesson outline.

In the first part of our learning, we are going to be looking at how 1000 can be composed of 100s and 200s, and in the second part of our learning, we are going to be solving problems using the composition of 1000.

Are we ready? Let's explore how 1000 can be composed of one 100s and 200s.

In this lesson, we are going to meet Sam, Sofia, Izzy and Lucas.

They're going to help us with our learning.

Are you ready guys? Sofia creates a bar model and asks Izzy how she could complete it.

Hmm, let's have a look.

What can we see? We can see that 1000 is the whole and we are partitioning it into five equal parts.

So Izzy knows that each part is worth 200.

How did you know that Izzy? Izzy knows that there are five twos in 10 and five 20 in 100.

So this fact is just 100 times and 10 times more.

Wow, I love that you used what you already knew Izzy.

Well done.

That's a really good useful skill to use.

Sofia now tests Izzy with this bar model, we can see that the whole is 1000 and we are partitioning it into 10 equal parts.

So each part must be worth 100.

That's right because remember when we were regrouping, 10 one 100s are equal to 1000.

It's the same knowledge.

Well done for remembering that Sofia, and well done Izzy for finding the missing parts.

Izzy and Sofia now explore this weighing scale face.

It looks just like the other ones, but what is different this time? We can see 1000 on our scale, but the parts are very different to what we've seen before.

There are five equal spaces between zero and 1000.

One, two, three, four, five equal parts.

So each part must be 200 because we can see this as 1000 divided by five.

Each division is worth 200.

So this one right here will be worth 200 grammes.

What would this one be? Let's have a look.

We can see that this is two more parts than 1000.

So I can see that this is 1000, 1,200, 1,400, because 400 more than 1000 is 1,400.

So that must be 1,400 grammes.

Well done Sofia and well done Izzy.

When we look at our scale face, we notice that we are now counting in our multiples of 200 because each division is worth 200 grammes.

Shall we have a practise at counting in our multiples of 200? We're going to start at zero and count in the multiples of 200.

Zero, 200, 400, 600, 800, 1000, 1,200, 1,400, 1,600, 1,800, 2000.

Well done.

When I was counting those, something sounded a little bit familiar to me.

If the arrow was pointing here then, how many more grammes would we need to have 2000 grammes? We can start here and we can count on to 2000.

We ready? 200, 400, 600, 800, 1000.

1,200, 1,400.

So that means we would need 1,400 grammes more to make 2000 grammes.

Wow, I can really see how counting in multiples of 200 can help me to read these scales.

We also know that six plus 14 is equal to 20.

So we know that 600 plus 1,400 must be equal to 2000.

So you didn't need to count in 200.

You could have used a calculation like Izzy.

Over to you then, Sofia records the multiples of 200 from 1000.

Can we fill in the missing numbers? Have a look at which parts are missing.

Do you notice a pattern that might help you to fill in those missing numbers? Pause this video, find the missing numbers and then come on back when you're ready to continue.

Welcome back, let's have a look then.

1000, 1,200.

So I know I'm counting in multiples of 200.

So 200 more will be 1,400, 1,600.

I'm seeing a pattern here.

I noticed that this pattern was going up in even numbers.

It was very similar to counting in my twos.

Two, four, six, eight.

So we go 1000, 1,200, 1,400, 1,600, 1,800 and then the next thousand.

That's the pattern that I noticed.

Did you notice the pattern? Izzy and Sofia now explore the hits on their school website over the weekend, Friday, Saturday, and Sunday.

But the graph looks a little different to what they've seen before.

How many visits did we get on Saturday? Let's have a look.

We can see that each 1000 has been split into five equal parts.

So we know that each part must be worth 200.

So let's have a look.

200, 400, 600, 800, 1000.

Thank you for that, Sofia.

That's really gonna help us to read our scale now because we know what the divisions in between are worth.

Let's have a look then, we can see that Saturday goes all the way up to there, which is 600.

So that means there were 600 hits on Saturday.

How many were there on Sunday Izzy? Izzy's added the rest of the numbers after 1000 to help her to read the scale.

Because look at Sunday, Sunday is huge.

Let's have a look then, it goes all the way up to there, which is 1,800 hits on Sunday.

Wow, I love how you checked how many divisions there were to help you know what each of those smaller divisions were worth.

Let's have a look then.

What was the total number of hits on Saturday and Sunday? So on Saturday we can see that there was 600 hits and on Sunday we can see that there was 1,800 hits.

So to find the total number, we need to add them together.

This is going to bridge 1000, so Izzy's going to use that strategy to help her.

1,800 plus 200 is equal to 2000 and 2000 plus 400 because we partitioned the 600 into 200 and 400 is two 400.

So that means that the total number of hits on Saturday and Sunday was 2,400 hits.

Goodness me, that's a lot of hits.

Well done Izzy, I love that calculating there.

Sofia now wants to know how many fewer hits there were on the website on Friday than on Saturday.

So let's have a look.

We can see that there were 200 hits on Friday and there were 600 hits on Saturday.

So to find the difference and find how many fewer we need to subtract 600, subtract 200.

We know that when we count in multiples of 200, 200 is one count.

So we just need to count backwards one count, 600, 400.

We can see that the difference between 600 and 200 is 400.

So that means that there were 400 fewer hits on Friday than on Saturday.

Well done Sofia.

I love how you use the counting in multiples there to help you.

That was a really efficient strategy, over to you then with task A.

Task A is to add the pointer to the scales to represent the mass of each of the prizes.

A, we have our panda that has a mass of 1,800 grammes.

B, we have a cowboy that has a mass of 1,400 grammes and finally C, we have a jelly blob and that has a mass of 600 grammes.

So using what you know, can you add the pointer to represent each of these masses? Pause this video and come on back once you've added them to the scales.

Welcome back.

Let's have a look at how you got on then.

Let's have a look at A, the panda.

The panda had a mass of 1,800 grammes.

On the scale we can see that there are five divisions between zero and 1000.

So each division must be worth 200 grammes.

We know that 800 grammes is four divisions of 200 grammes.

So four divisions after 1000 will be 1,800 grammes because 1000 plus 800 is equal to 1,800.

So your pointer should have been one, two, three, four more divisions than 1000, which is right there.

Well done if you got that one correct.

Let's have a look at B then.

B, our cowboy had a mass of 1,400 grammes.

The pointer would go all the way up to here.

That's because we know that 400 grammes is two divisions of 200 grammes.

So two divisions after 1000 will be 1,400 grammes.

1000 plus 400 is equal to 1,400.

So we would have 1200, 1400, well done if you got that one correct.

And finally C, let's have a look at our jelly blob.

Our jelly blob had a mass of 600 grammes.

So what do we know already? We know that 600 grammes is three divisions of 200 grammes, so that means it's going to be three divisions from zero.

It's going to go there.

Well done to you for completing task A.

In the second part of our learning, we're going to solve problems using our knowledge of the composition of 1000.

Sofia and Izzy make some juice to enjoy.

They want to know how much juice they have, but they've got a problem.

What do you think their problem could be? Sofia has noticed that they only have 1000 millilitres labelled on this jug, so we can't see how much juice there is.

Izzy suggests that they can use their knowledge of 1000 to estimate how much juice is in the jug.

Hmm, that's a lovely idea, Izzy.

So let's have a think about what we know about the composition of 1000 that might help us to read the scale.

We know that 500 millilitres would be there because two 500s is equal to 1000 and half of 1000 is equal to 500 millilitres.

But our juice is an at 500 millilitres.

Where is it? Sofia notices that it's in between 1,500 millilitres, so she partitions the scale into four equal parts.

That means that each division is worth 250.

So we can now see that we have 750 mils of juice.

Well done girls.

I love how you use your knowledge of the composition of 1000 there to help you read that jug scale.

Let's have a look at another one.

Sofia and Izzy pour themselves a drink from the juice and estimate how much juice they have left.

First, Sofia's going to add on 500 millilitres because that's going to help her place other measures on the scale to help her and we know that 500 millilitres is halfway between zero and 1000.

We can see that there is less than 500 millilitres.

So what other divisions could we put on our scale? Izzy suggests that we put on the 250 divisions onto our scale.

Let's have a look.

Oh, our juice is still more than 250, so that wouldn't be a good estimate.

What are the divisions could we think about? Oh, that's a good idea Sofia.

Sofia now thinks of a hundred millilitre divisions because she knows that there are 10 100s in 1000.

Let's have a look then.

Sofia estimates that this is going to be around 400 millilitres after putting the hundred millilitre divisions on her scale.

What do you think Izzy? Izzy didn't think about 100 millilitre divisions.

She thought about 200 millilitre divisions because we know that that divides our scale into five equal parts and Izzy can also see that 400 millilitres would be a good estimate for how much juice they have left.

Well done guys, I love that you work through all of that composition of 1000 knowledge until you worked out what would be a good estimate.

Well done, over to you then.

Use your knowledge to estimate the amount of juice that might be in this jug.

What knowledge could you use from your composition of 1000 knowledge to help you to work out what would be a good estimate of how much juice is in our jug? Pause this video.

Have an explore and come on back when you think you've got an estimate.

Welcome back, come on then Sofia.

Let's have a look at what you were thinking.

Sofia noticed that the juice was close to 900 millilitres but not as low as 750 millilitres.

So she estimated that this was around 900 millilitres.

Let's have a look.

Let's pop on our 100 millilitre divisions to see if she's close.

Yes, Sofia, well done.

900 would be a good estimate because look, it's more than 750 millilitres and less than 1000 millilitres, but it's closer to 1000 than it is to 750, so that would be a good estimate.

Izzy and Sofia now apply their knowledge to this problem.

Where would 400 grammes go on this scale? Hmm, I'm not sure about this.

I've not seen a problem like this before.

Oh, of course Sofia.

It looks just like the scales that we've used on the jugs, but this one is horizontal instead of vertical, a good spot there, Sofia.

That means we can use all of our great learning just like we've just done at working out how much juice was in the jugs.

Izzy has noticed that the scale is from zero to 2000 instead of 1000 like the jug.

So what does that mean? They're going to apply their knowledge of 1000 to work on the scale that goes up to 2000, but what knowledge could they use? We know that two 1000s is equal to 2000.

So 1000 would be right in the middle of this scale because we can split it into two equal parts.

1000 and 1000, because now at least we know which part of our scale 400 grammes will fall on.

Then we know that if we divide this half into two equal parts, that will be 500 because two 500s are equal to 1000.

Well done Izzy.

I love how you use that knowledge there to help you to put another marker on our scale.

So now we have zero grammes, 500 grammes and 1000 grammes that can now help us to find out where 400 would go.

We know that 400 grammes will definitely be on this part of our scale because it's less than 500 grammes.

We can now think of divisions of 100 because that will help us to see where 400 would be.

We know that there are five one 100s in 500, so we can estimate that 400 grammes will be around there because we can imagine that that part has been split into five equal parts.

Well done Izzy and well done Sofia, I love how you narrowed down using that knowledge there to help you to pop 400 grammes onto our scale over to you.

Then where would you place 1,600 grammes on this scale? You can use some of the knowledge that Sofia and Izzy have just used to work out theirs to help you pause this video and come on back once you've managed to add 1,600 grammes onto the scale.

Welcome back, let's have a look then at how you got on.

We know that two 1000 is equal to 2000, so we know that 1000 grammes would go right in the middle of the scale.

Now we can see where we need to look to add 1,600 grammes.

We know that 1,600 grammes will be on this part of our scale.

We can divide this half into two equal parts because that will be 500 more than 1000 because two 500s make 1000.

So here will be 1,500 grammes.

Now 1,600 grammes is going to fall in this part here because it's 100 grammes more than 1,500 grammes.

Let's divide that part into five equal parts because that will show us where 100 grammes more would fall.

We can estimate that 1,600 grammes will be around there.

Well done to you if you manage to put 1,600 grammes around there on our scale.

Sofia and Izzy now have a look at this kind of scale.

Ooh, this looks like a weighing scale to me that you might use in your kitchen.

The question is how many more grammes do they need to make 2000 grammes? We don't have any divisions on our scale.

What are we going to do? We know that we need less than 1000 grammes because 1000 grammes is there on our scale and our market is past that and we know that we need more than 500 grammes because 1,500 grammes is there and we need more than that to make 2000.

How are we going to work this out then? Sofia suggests that we figure out what the mass actually is.

Then we can work out how much more we need.

Izzy pops on the division of 1,250 because she knows that the large division is 500, so the midpoint will be 250 more.

The pointer is just a little less than 1,250 grammes.

So Izzy estimates that we have around 1,200 grammes on that scale.

So how much more do we need to make 2000.

We currently have 1,200 grammes and we know that we need to add 800 grammes more to make 2000 grammes.

So 800 grammes would be a good estimate at how many more grammes we need to make 2000.

Well done Izzy and well done Sofia.

Now over to you.

How many more grammes do we need here to make 2000 grammes? Think about what you already know and use this to help you to work out how many more we need.

Pause this video, have an estimate using what you know and come on back when you're ready to continue.

Welcome back, let's have a look then.

Girls, what knowledge did you use to help you here? We know that 1000 grammes would be around here and 500 grammes would be around there because when we partition zero to 1000 into two equal parts, 500 would be in the middle.

We can see that this pointer is just a little more than 500.

So a good estimate would be around 600 grammes.

Now, how many more grammes do we need to make 2000 grammes? That's the question.

So 400 grammes more would equal to 1000 grammes and 1000 grammes more would equal to 2000 grammes more.

400 grammes plus 1000 grammes is equal to 1,400 grammes.

So a good estimate would be 1,400 grammes more to make 2000 grammes, well done if your answer was around 1,400 grammes.

Over to you then with task B, the children end the day with a go on the Strength O Metre.

Look, the Strength O Metre has a blank scale just like we've been looking at.

So it does Lucas, a good spot.

Task B is for you to solve some problems using the children's results on a bar graph.

Use your knowledge of estimating in blank scales to read the number lines and solve the following.

A, estimate each child's score on the strength O metre.

B, estimate the sum of Lucas and Izzy's score and C, estimate the difference between Sam and Sofia's scores.

So if you can see here, this is bringing all of your learning together.

So pause this video, have a go at task B and come on back when you're ready to finish the learning.

Welcome back.

I hope you enjoyed bringing all of your learning together there.

Shall we have a look how we got on? So part A was to estimate each child's score on the strength O metre.

Sofia we can see is in the middle of 1000 and 2000.

So we know that a good estimate for this score would be 1,500.

Izzy is in the middle of 1000 and 1,500, which we know is 1,250.

Izzy's score is is slightly less than 1,250.

So a good estimate would be 1,200.

Well done if you said this.

Let's have a look at Sam then.

Sam is in the middle of 1,500 and 2,000.

So a good estimate would be around 1,750 and Lucas we can see is more than 500 and a little more than 750.

So around 800 would be a good estimate for Lucas's score.

Well done if you were close to these estimates.

B was estimate the sum of Lucas and Izzy's score.

Lucas' estimated score was around 800 and Izzy's estimated score was 1,200.

1,200 plus 800.

Let's have a look then, I can see that 800 plus 200 is a number bond to 1000.

So 1,200 plus 800 is equal to 2000.

Adding 800 is four counts on in multiples of 200.

So we could have counted on, but the most efficient strategy there was to use my knowledge of number bonds to 1000.

Well done if your score was around 2000.

C, estimate the difference between Sam and Sofia's score.

Sam's estimated score was 1,750.

Sofia's estimated score was 1,500.

1,750 subtract 1,500 will give me the difference.

We know that 1,750 is the number after 1,500 when we are counting in multiples of 250.

So that means that the difference between 1,750 and Izzy's score of 1,500 must be 250.

Well done if your estimate was around 250.

Well done for completing task B and finishing your lesson.

Let's have a look at what we've covered today.

There are 10 one 100s in 1000.

There are five 200s in 1000.

Knowing how many one 100s and 200s 1000 is composed of helps us to interpret scales and measures.

Knowing the composition of 1000 can help us to work out the meaning of each division on scales and number lines, and we can use our knowledge of divisions on a scale to then estimate.

Thank you so much for all of your hard work today.

I hope you've enjoyed your learning and I can't wait to see you all again soon, goodbye.