# 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 revisiting some of the concepts that we covered in the unit, Numbers to 100.

Let's get started.

For our session today, you will need a pencil and rubber, some paper, and you are also going to need some countable objects like these that you can use to represent tens and ones.

So pause this video and get the equipment that you need, if you have not got these things already.

Our lesson agenda for today looks something like this.

We're going to start off our learning by partitioning numbers in different ways.

Then we're going to look at finding 100.

Next, we're going to recap ordering numbers to 100.

And finally, you will have your quiz to take at the end of the lesson where you can recap everything that you've learnt in today's session.

So to begin our lesson today, I want you to look at the words in the middle of my screen, that represent different numbers.

I've made a few mistakes and I need you to help me out by spotting my spelling mistakes.

Pause the video now to complete this task and press Play when you're ready to continue.

Right team, let's have a look at these then.

In the top one, we should spell 67 with a T, a T was missing there.

33, 41, 12, 14 and 50.

So just check to see if you've got them all.

So there was a mistake in every single one of them.

Well done, if you managed to spot all of my spelling mistakes.

So, as we mentioned in our lesson agenda, the first part of the lesson today is going to look at partitioning two digit numbers using a part-whole model like this.

So, the two digit number that we're going to be partitioning today in a part-whole model is the number 64.

So, 64 is our whole.

Because it's our whole, I'm going to represent 64 with dienes here in the whole part of our part-whole model.

So let's just count our representation to double-check we've got 64.

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

Brilliant, I've got 64, which represents my whole.

Remember, that when we are using a part-whole model to represent a two digit number, we are splitting our whole into tens and into ones.

So here, 64 has six tens and four ones.

So I've got my six tens here, 10, 20, 30, 40, 50, 60, and my ones here.

Let's represent this in digits now.

So here's my part-whole model.

Remember 64 is our whole, so that goes in there.

This part represents my tens.

And remember 64 has six tens.

So, I'm going to have 60 in there, because the value of six tens is 60 and 64 has four ones.

So four, will go in this one's part here.

This part-whole model is showing us that 64, our whole is equal to our two parts, 60 and four added together.

So, 64 is equal to 60 add four.

I can switch around my parts in the equation like this, because it doesn't change the value of my whole, where the four is in here and 60 is in here, it's not going to affect my whole value.

So 64, is also equal to four add six.

Now that we have these two representations of our number 64, we can think about representing the number differently by partitioning it in different ways.

For example, I could move one 10 from this part and move it here like this.

You will notice I still have the same number of tens and the same number of ones that I started with.

So my whole 64, has not changed.

However, the values of my parts has changed.

In this part, I now have five ones instead of six ones.

So the value of this part is 10, 20, 30, 40, 50.

And in this part, I have one 10 and four ones.

So the value of this part is 10, 11, 12, 13, 14.

But to represent that in digits, we know that this part is now going to be worth 50, and this part is now going to be worth 14, but my whole does not change, because I've not added or taken anything away.

I've just moved my parts around.

I can show this in an equation.

So this tells me that 64 is equal to the parts 50 and 14 added together.

So I can also make 54 with the numbers, 50 and 14.

Let's try partitioning our number 64 in another way now.

I'm going to move another one of these tens into this part.

So again, my whole is not changing because I'm not taking away or adding any tens or ones.

All that's changing is the values of my parts because I'm just moving the tens into a different part.

So now in this part, I have one, two, three, four tens, which has the value of 40, 10, 20, 30, 40.

So this value is now 40.

And here I now have two tens and four ones, 10, 20, 21, 22, 23, 24.

So, the value of this part now is 24.

So I can also make our whole 64 by adding together the two parts 40 and 24.

I can show you this in my equation, 64 is equal to 40 add 24.

You are now going to have a go at partitioning our two digit number 43 using dienes and digits, just as we've looked at in our previous learning.

I would like to see how many different combinations you can partition 43 in.

And I would like you to write them out as the equations.

And resume the video when you're finished and ready to continue.

Okay, let's have a look then at the different combinations you could have had for the number 43.

43 could have been partitioned into 40 and three.

30 and 13, 20 and 23, 10 and 33.

And if you'd moved all of your tens into the other part, zero and 43.

So give yourself a tick for each of these equations if you got them.

Good job.

In this next part of the lesson, we are going to look at how we can make 100 using dienes and a part-whole model.

On this screen, you can see that I have a 10-stick, which presents the number 10.

I want to know what do I need to add to 10 to make 100? Hmm, well, we know that the number 100 is equal to 10 groups of 10, And that looks like this.

So here I've got 10, 20, 30, 40, 50, 60, 70, 80, 90, 100.

These 10 groups of 10 add up to make 100.

I already have one group of 10 here, one stick of 10.

And I can see from this image that I will need nine more groups of 10 to make 10 in total.

Let's count out again, how many I need.

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

So I need nine more groups of 10.

Let's represent this in a part-whole model.

So here's my part-whole model.

The whole number that I'm trying to get to is 100.

I have 10 already, 'cause I've got one 10-stick, and we know that I need nine more groups of ten to make 100 in total.

So that's the value of 90, because nine groups of 10, I can count like this 10, 20, 30, 40, 50, 60, 70, 80, 90.

So nine tens is equal to 90.

So, I know that 10, the 10 I had, add on 90 is 100.

So, to make 100, I need to add 90 to this 10-stick.

Let's try another one.

Okay, so on the screen, I've got three 10-sticks, which have the value of 30, 10, 20, 30.

And again, I want to know what do I need to add to 30, to make 100? Well, we know that 100 is equal to 10 groups of 10.

At the moment, I've got three groups of 10.

Let's have a look at what 10 groups of 10 looks like.

Okay, it looks like this.

And I know I've already got three of them.

So let's count how many more I need.

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

So I need seven, one, two, three, four, five, six, seven more sticks of 10.

And the value of seven sticks of 10 is 70.

Let's put that in a part-whole model.

So the whole that we're trying to make is 100.

We're finding 100 at the moment.

And I know that I need seven sticks of 10 more to get my 10 groups of 10, which is 100.

Seven tens is equal to 70.

So I know that I need to add 70 to 30 to get my whole 100.

In an equation that would look like this.

30 add 70 is equal to 100.

Now on my screen, I have five sticks of 10 and six ones, which represents the number 56.

10, 20, 30, 40, 50, 51, 52, 53, 54, 55, 56.

And again, I want to know what do I need to add to 56 to get to 100? Well, we know that 100 is equal to 10 groups of 10, which looks like this as a total.

Okay, I've got 10, 20, 30, 40, 50, 60, 70, 80, 90, 100.

I've got my 10 groups of 10, which equals 100.

I know that I already have five groups of 10 and six ones.

So here are my five sticks of 10, 10, 20, 30, 40, 50, and six ones, 51, 52, 53, 54, 55, 56.

So I can see from this representation that I still need one, two, three, four sticks of ten and one, two, three, four ones to get my number to 100.

Let's count these one more time.

10, 20, 30, 40, 41, 42, 43, 44.

So I know that I need 44, I need to add a part worth 44 to my part 56, to get 100.

Let's look at that in a part-whole model.

So my whole is 100.

The part in green that I already had was 56 and I was trying to work out what this missing part was.

And we worked out from this diagram that I need 44 more to get to 100.

So you've been given the number 35 in dienes, and I would like you to just use the same methods to figure out what you need to add to 35, to make 100 altogether.

Remember, that 100 is equal to 10 groups of 10.

Pause the video now to complete your task and resume the video once you are finished.

Good work guys.

So, you were looking to see how much you needed to add to 35 to make 100 altogether.

We know that 100 is 10 groups of 10.

So this is what 100 looks like.

And we have 30, a part of 35 already.

So 10, 20, 30, 31, 32, 33, 34, 35.

So, looking at this diagram I can see that I still need 10, 20, 30, 40, 50, 60, 61, 62, 63, 64, 65 to add to my 35, to get 100 all together.

In a part-whole model that would look like this.

100 is the whole, 35 was the part that we started with the green part, and 65 is the part that was missing that we need to add to 35 to make 100.

So 35 add 65 is equal to 100.

In this final part of the lesson team, we're going to recap ordering numbers to 100.

So I want you to have a look at the sequence of numbers that are on my screen.

I want to know if they are in increasing order or decreasing order.

To find this out, I'm going to make my numbers using dienes so I can see their representations clearly.

So, here are my part-whole models that I can use.

26 is made up of two tens and six ones, 21 is made up two tens and one one, 20 is made up of two tens, 16 is made up of one 10 and six ones, and 12 is made up of one 10 and two ones.

Okay, so looking at my representations, I can see that the greatest number that I have in my sequence is the number 26, which comes first.

I know that this is the greatest number, because it's got two tens, which is more than one 10, that 12 and 16 has, and it's got six ones, which is greater than the number of ones that 21 has.

Okay, and that 20 has.

So I know that 26 is the greatest, 21 is then ever so slightly smaller because it's got less ones, 20 is smaller than 21 because it's got no ones, and then we get down to 12, which is the smallest number, because it's got less ones than 16 and less tens than all of the other numbers.

So I know that these numbers in this sequence are decreasing, they're getting smaller each time.

Okay guys, this is your first independent task of ordering numbers within 100.

So you're going to take these two sequences and decide if they are increasing in order or decreasing in order.

Once you've completed that task, there was a second independent task for you to do, where you've been given representations of numbers, and you need to put those in decreasing order.

Pause the video now to complete your tasks and resume the video once you are finished and ready to continue.

Welcome back team, great job.

Let's go through these answers then.

So I can tell from looking at this sequence that these numbers are decreasing because 90 is the greatest number with nine tens, 80 is smaller, because it's got eight tens, 70 is smaller than that, because it's got seven tens, 17 is smaller than that, because it's only got one 10, And seven hasn't got any tens at all.

So going down my sequence, the numbers are getting smaller, so they are decreasing.

Looking at the next one, they all have the same number of tens, so I need to look at the ones to help me compare them.

99 has nine ones, 98 has eight ones, 95 has five ones, 92 has two ones, and 90 has zero ones.

So I can also see that this sequence is decreasing.

My numbers are getting smaller each time.

In this independent task, you had to work out what the representations were and then order their numbers.

So this number 81, 81 is the greatest number, that needs to go first, because our numbers are going in decreasing order.

So the biggest number has to go first and then all of my numbers can get smaller after that.

So it should have gone 81, 44, 41 and 14.

Great job, if you've got those answers team, well done, All that's left for you to do now is to complete your quiz.

So when the video has ended, don't forget to take part in the quiz to recap everything you've learnt and to show off everything you can remember from today's session and our unit, Numbers within 100.

Team, that concludes our lesson for today.

Well done on another great session, and I hope to see you very soon, bye-bye! If you'd like to, please ask your parent or carer to share your work on Instagram, Facebook, or Twitter tagging @OakNational and #LearnwithOak.