# Lesson video

In progress...

Hello, everybody, and welcome to today's session.

My name is Miss Hughes and in today's lesson, we're going to be looking at partitioning 2-digit numbers as part of our unit Numbers Within 100.

So let's get going.

For today's lesson you will need a pencil, some paper and some countable objects to represent tens and ones.

Pasta works really well if you've not got dienes or cubes or counters at home.

You can also draw your tens and ones too.

Please pause the video now to go and get these things if you haven't got them already.

Okay, great, team.

Let's have a look at our lesson agenda for today to see our learning journey for today's lesson.

We're going to start off by partitioning numbers into tens and ones as part of our new learning.

Then we're going to partition with dienes in a part whole model.

We'll move on to look at canonical partitioning.

Then you're going to have an independent task and we'll go through the answers.

And finally, of course, you have your quiz where we can remember or we can see everything you have remembered from today's lesson.

Okey-docks.

We are going to start off today's lesson then by looking at an image on the slide.

So it's an image of a market stall.

And I want you to just focus on the bananas on the stall, which are round here.

Have a think about my questions there on the slide.

How many bananas are there altogether? And what might be an efficient way to count the number of bananas that are on the slide.

Or these questions, sorry.

And then play when you are ready to continue.

Okay.

So I'm going to count the number of bananas that we have by counting them in bunches of tens on the single bananas in ones.

It's much more efficient to count the bananas in tens and ones than count them all individually.

So let's get started.

We've got 10, 20, 30, 40, 50, 60, 70, 71, 72, 73, 74, 75, 76, 77, 78.

So there are 78 bananas altogether.

We can show this in a part whole model.

Here is my part whole model.

And we have our whole, which is 78 bananas here.

That was the number of bananas I have altogether in total.

But I'll just count them first one more time to check if that's the right amount.

So 10, 20, 30, 40, 50, 60, 70, 71, 72, 73, 74, 75, 76, 77, 78.

That is a lot of bananas, isn't it? Okay, so great.

I've got my 78 bananas altogether here.

So 78 is my whole.

And I can partition my whole into tens and ones.

So I'm going to put the bunches of 10 bananas into this part.

10, 20, 30, 40, 50, 60, 70 bananas.

And the single bananas can go into this section, in my ones.

One, two, three, four, five, six, seven, eight.

Fantastic.

So now I have partitioned my whole 78 into two parts.

The tens, which are up here, and the ones.

Let's have a look at the value of each part now.

In this section, I have seven bunches of 10.

So this part is worth 70.

The other part is worth eight because there are eight ones in it.

When I add both of my parts together, 70 and eight, I will get the whole amount that I started with.

70 add eight is equal to 78.

I can also, my apologies.

I can also rewrite my equation in this way starting with my whole.

78, which is equal to 70 add eight.

Even if I start with my whole, the values remain the same.

So even if 78 is the beginning here I still am adding 70 and eight.

Let's look at how we can put our oranges.

Let's look at how we can put our oranges in the market stall into a part whole model.

We're going to ignore this big box of oranges at the back and just look at these ones at the front that I've highlighted in red.

Okay, so we've got 10, 20, 30, 31, 32, 33, 34, 35 oranges.

Now we're going to put it into a part whole model.

Which looks like this.

So here is my big part whole model with my 35 oranges in it.

So you can see I've got my 10, 20, 30, 31, 32, 33, 34, 35.

My whole is 35.

Now we can partition our whole into the different paths.

So the bags of 10 oranges will go into this part.

So that's 10, 20, 30.

And the single oranges will go down in this part.

One, two, three, four, five.

So now we've partitioned our whole 35 into two parts, which represent 30 and five.

I can also represent these oranges in this way using dienes.

So in this part, I have three lots of 10 up here.

So that's one lots of 10, two lots of 10, three lots of 10.

And I can put my ones down here to represent my oranges.

One, two, three, four, five.

Now this shows me that 35 is equal to 30 add five.

Or 30 add five is equal to 35.

The whole, in other words, is equal to my two parts added together.

So the whole is 35 and it is equal to 30 add five, which is my separate parts.

Right, team, it's time to put this into practise with a talk task.

So you will be given an image of some fruit, a bit like this one that I've got on the board.

And your task is to partition the amount of fruit into a part whole model like I've got below.

So partitioning it into its tens part and its ones part.

There're going to be some sentence structures that I would like you to use to support your explanation of this.

I'm going to model this one for you and then it will be your turn.

Okay? So let's get up the first sentence structure.

I'm going to count the apples.

10, 20, 30.

31, 32, 33, 34.

There are 34 apples.

The whole is 34.

I've put my 34 in the whole down here.

Let's look at the next sentence structure.

I'm going to make the whole with 10 sticks.

10, 20, 30 and ones.

31, 32, 33, 34.

So I've partitioned 34 into tens and ones.

One part is worth 30.

Sorry.

One part is worth 30, and the other part has a value of four.

34 is equal to 30 add four.

Okay, so you can see that I used my picture.

I used dienes to partition my part whole model.

And I used my sentence structures to give my explanation.

You are now going to use the same sentence structures to have a go at these questions yourself.

So pause the video now to complete your task and then press Play when you are ready to continue.

Okay, welcome back, team.

How'd you guys get on? Are you ready for the answers? Right, let's go through them now then.

So let's have a look at this first one at the top.

I'm going to count the apples.

10, 20, 30, 40, 50, 60, 61, 62, 63, 64, 65, 66, 67.

My whole is 67.

So I'm going to make the whole with 10 sticks.

10, 20, 30, 40, 50, 60.

And I've partitioned them into tens and ones.

61, 62, 63, 64, 65, 66, 67.

So I've partitioned my whole into two parts.

One part is worth 60.

One part is worth four.

Sorry, one part is worth seven.

So 60 add seven is equal to 67.

Let's look at the next one.

So we've counted our carrots.

10, 20, 30, 40, 50, 60, 61.

There are 61 carrots.

The whole is 61.

I'm going to make the whole with six 10 sticks.

10, 20, 30, 40, 50, 60.

And one one.

61.

I'm going to partition the 61 into tens and ones.

One part is worth 60.

One part is worth one.

So 61 is equal to 60 add one.

I'm going to count my carrots.

10, 20, 30, 40, 50, 60, 70, 71, 72, 73, 74, 75, 76.

There are 76 carrots.

The whole is 76.

I'm going to make the whole with 10 sticks.

10, 20, 30, 40, 50, 60, 70.

And ones.

71, 72, 73, 74, 75, 76.

Let's look at this last one then.

So I'm going to count the apples.

10, 20, 30, 40, 50.

There are 50 apples.

The whole is 50.

I'm going to make the whole with 10 sticks.

10, 20, 30, 40, 50.

And no ones because I didn't have any ones left over in that image.

Now I'm going to partition the 50 into tens.

So here are my five tens.

So one part is worth 50.

And the other part has a value of zero because I haven't got any ones down here.

So 50, my whole is equal to 50 add zero.

Let's move on to our develop learning now.

We have a 2-digit number here, which is 45.

Okay.

And I want to know how we can represent this number using dienes.

So let's think about using our part whole model.

Okay, here it is.

Here's my part whole model.

45 has four tens and five ones because the value of the digit four is 40, and the value of the digit five is worth five ones.

So five.

Because 45 is my whole, I'm going to put these into the whole section like this.

Now I can partition 45 into tens and ones.

So there are four tens here, and they are going to go into that part.

And there are five ones, which will go into this part.

The four tens is 40, and the five ones is five.

So 40 add five equals 45 like this.

My two parts, 40 and five.

If I add them together, I will get my whole 45.

Remember I can also write it this way round.

It doesn't matter what way round I say these.

I still end up with the same whole even though my parts are switched around.

So my 40 can be down here, and my five can be up here.

Even though I've switched them over, my whole is still the same.

This is because of something called commutative law, which means that I can change the order of my parts in an equation, but it will not change the whole.

Can you try saying communicative law? I'll go first.

Communicative law.

Awesome.

It's really important to remember that 45 is not five tens and four ones like this.

Okay, so that's five tens and four ones.

If I have five tens, that would be 50, and four ones would be four because 10, 20, 30, 40, 50, five tens is 50, and one, two, three, four is four.

We can also represent our number 45 in a place value chart, which looks something like this.

It's got columns with the two headings, tens and ones.

So if we look back at our part whole model where we've partitioned our whole 45 into tens and ones, we can use that to help us partition our number into tens and ones in our place value chart.

So looking at this representation here, it's really clear to see that 45 is made up of four tens in this part and five ones.

So all I need to do here is put a four in my tens column because that represents four tens.

And you've probably guessed already that five will go in the ones column because that represents five ones.

So I've got four tens and five ones in this representation.

Okay, team, great work.

We're now going to move on to the independent task now.

So just like we were doing in our develop learning, for today's independent task, you are going to be given a number of 2-digit numbers like this one, 54.

And what I would like you to do with those numbers is partition them into tens and ones in a part whole model like this one, in a place value chart like this one, and then write an equation to represent the partitioned parts and how they are together to make the whole.

Okay, for this task you're going to need some countable objects that you can use to represent your tens and your ones.

In the develop learning, you saw that I used dienes, but if you don't have dienes at home, you can use something else.

So maybe you have some counters or some Lego.

You might have some cubes.

Or if you haven't got any of those things you can even use something like pasta, to represent your tens and ones.

Then what I want you to do is write the correct digits in the place value chart and, as I said earlier, write an equation.

So let's go through this one first and then I'm going to let you get on with your own ones.

So I have the 2-digit number 54 here.

So that is my whole.

So I need to put it in the whole section of my part whole model here.

Now I'm going to partition it and use dienes to represent the tens and ones.

So 54 has five tens.

I've got them there.

One, two, three, four, five.

And four ones, one, two, three, four.

You could draw these if you don't have any countable objects and that's fine, too.

Five tens I know represents 50.

And because I've got five tens here, I can put a five in my tens column to represent the five tens.

In my ones column, I'm going to put the digit four because that represents four ones because I've got four ones down here in this partition.

So I know that 50 add four is equal to 54, and that will be that task finished.

Okay? These are the ones that I would like you to try today.

Once you have completed these tasks I have a challenge for you.

So this is the challenge.

For this task, you've been given the parts of a whole and you need to figure out what the whole is.

Okay.

So once you finish your independent task I'd like you to have a go at this challenge.

Pause the video now to complete your task and resume the video once you're finished and ready to continue.

Welcome back team.

Let's have a look at these answers then.

So in this first example, we have the number 64.

So that is my whole.

And I know that 64 is made up of six tens, which is 60, and four ones.

So I'm going to put six in the tens column of my place value chart, four in the ones column of my place value chart, and that represents that 60 add four equals 64.

Let's look at the next one.

46 is the whole, and it's made up of four tens and six ones, which I've put in my place value chart, which means that 40 add six is equal to 46.

72 is the next one.

So 72 is my whole.

72 is made up of seven tens and two ones.

So I put my seven tens in here and my two to represent my two ones in here.

Seven tens is worth 70.

So 70 add two equals 72.

And this one at the bottom.

53 is the whole, which is made up of five tens and three ones.

So I've put five in the tens column and three in the ones column to represent those.

Five tens is worth 50 and three ones is worth three.

So 50 add three together make my whole 53.

35 is the next one that's made up of three tens and five ones.

So I've put that in my place value columns.

30 add five is equal to 35.

Lastly, 27 is the whole, which is made up of two tens and seven ones, and I've put them in my place value chart.

Two tens is worth 20 and seven ones is worth seven.

So 20 add seven is equal to 27.

Okay, and onto the challenge answers.

So remember that in a part whole model, if we add our two parts together we will make our whole.

So what I need to do is add all my two parts together to realise what the whole is.

So 20 add six is 26.

And 90 add five gives me 95 as a whole.

Well done if you got to those challenge questions.

Fantastic.

Okay, team.

That is it for our learning today.

And I'm so impressed with all of the fantastic thinking and listening and hard work that you put into today's session.

I look forward to seeing you on another session soon.

Bye-bye.

Once the video has ended don't forget to go and complete the final quiz.

I'm really excited to see all of the fantastic learning that you've remembered from today's session.

So good luck and see you soon! If you'd like to, please ask your parent or carer to share your work on Twitter tagging @OakNational and hashtag LearnwithOak.