Lesson video

Hello everybody, my name is Miss Hughes and welcome to today's lesson where our objective is going to be exploring odd and even numbers.

Let's get going.

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

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

Okay team, our lesson agenda for today is going to start with making two digit numbers.

Then we're going to go on to represent two digit numbers.

You will then have an independent task to complete.

And then of course at the very end, there'll be a quiz for you to do.

And that is to see how much you have remembered from today's lesson.

In our session for today, we are going to use all that we have learned about place value so far in this unit to help us solve problems. First, I have some number cards here that are faced down.

I'm going to pick two at random.

Okay, so my digits are two and seven.

I want to know what 2-digit number or numbers I can make with these digits two and seven.

Have a quick think in your head.

I'm going to give you a few seconds for this.

What numbers can we make with the digit two and seven? Have you thought of one? Brilliant let's have a look at them then.

So using my place value chart, I could represent the number 27.

To make 27 I will need two to go in the tens column.

And I will need seven to go in the ones column.

I could represent the number 27 in Dienes as well.

So obviously in Dienes I'm going to need two tens because my two digit is in the tens columns that represents two tens, is one, two or 10, 20 and I'm going to need seven once because my digit seven is in the ones column in the number 27.

So then my seven once.

Let's count them to be sure that we've got the number 27 here, 10, 20, 21, 22, 23, 24, 25, 26, 27, fantastic.

So this is my number 27 but presented in Dienes.

Can we move the digit two and seven around if we wanted to to make a new number? If so, what would my new number be? I'm going to give you five seconds of thinking time.

I can swap around my two digits, two and seven, and this would change their values.

Therefore, my 2-digit number would change as well.

So I can change my two and seven around.

I can swap them over.

So seven is now in the tens column and two is now in the ones column.

If I switched them around like this, I'm going to have a different representation of Dienes.

So let's see what that would look like.

So I've got seven in the tens column now, which means I need seven tens, 10, 20, 30, 40, 50, 60, 70.

Those are my seven tens and I have two in the ones column.

So I'm going to need two once, 71, 72.

So my new number having switched around my digits is 72.

We're going to now look at the different ways we can represent these 2-digit numbers, 27 and 72 using different resources.

So we've seen how they would be represented using digits like this with numbers and Dienes like this.

What about a Part-Whole model? The number 72 here is our whole.

So that is our whole.

It needs to be partitioned into tens and ones, and we know they need to be seven tens in here and two ones in here.

So 72 would be partitioned in this way because seven tens is equal to 70.

So this tens part has a value of 70 and two ones has a value of two.

If we add our two parts together, 70 and two, we will get our whole 72.

So I could represent that as an equation as well.

72 which is our whole is equal to our parts 70 add two.

So my two parts added together make my whole.

Let's have a go at representing 27 in a Part-Whole model now then.

So 27 is our whole and it needs to be partitioned into tens and ones.

Two tens has a value of 20.

So this part is going to be worth 20 and seven ones has a value of seven.

So that part is going to be worth seven.

So our whole 27, we can make that by adding our two parts 20 and seven together.

And remember I can write that as an equation.

So that would look like 27 is equal to 20 add seven.

In other words, my hole is equal to my first part add my second part.

Let's now have a look about how we can represent these two numbers once again in another different way.

Hmm.

What would they look like if we presented them on a number line? So here is my number line and let's think about the number 72 first.

Well, 72 has seven tens.

That means that I'm going to need to make seven jumps of 10 on my number line.

One, two, three, four, five, six, seven, that's seven jumps of 10 there.

Let's get counting tens to see what value that is 10, 20, 30, 40, 50, 60, 70, great seven jumps of 10 equals 70.

Remember 72 also has two ones.

So now I need to do two jumps of one, 71, 72.

So this is what 72 would look like on a number line.

Let's have a go at representing 27 now.

So here's my number line, 27 has two tens.

So I'm going to need to do two jumps of ten one, two or for skip counting in tens 10, 20 and seven once.

So I'm going to need to do seven jumps of one 21, 22, 23, 24, 25, 26, 27.

Brilliant, so that is what 27 would look like on a number line.

Now that we've thought through about our two numbers in a lot of detail and represented them in different ways.

I want us to think about this question, which number is greatest? Mhh.

When we're deciding which number is greatest, Can you remember which digit we should look at first? Is it the tens or the ones when I'm comparing my 2-digit numbers? Have a few seconds to think.

That's right.

It's I need to look at my tens first.

So looking at my tens, I can tell that 72 is the greater number because seven tens is greater than just two tens.

And you can see that in my representation of Dienes there are more tens here because I've got seven of them than over here, because over here I've only got two tens.

I do not need to go and look at the ones column or the ones digits here because I can tell already from my tens that this number is greater, the 72 is greater.

So we know that 72 is the greatest number out of these two.

What odd and even numbers can we make from these digits seven and two? Well, we know already from what we've been doing on new learning that the two 2-digit numbers we can make with these 2-digit cards are 72 and 27.

So let's get them on the screen.

To find if the number is odd or even we need to look specifically at the ones column to help us identify if a number is odd or even.

So I'm going be looking in both numbers at my ones column.

It's only this digit that can tell me if the number is odd or even.

I can see that 72 is an even number because the digit in the ones column is two, because two is a number that can be divided exactly by two, I know that it is even.

Therefore my whole number 72 is even.

Let's have a look on number 27 now.

Remember we looked at our ones to decide if a number is odd or even.

Hmm.

In the ones column here for the number 27, I've got the number seven.

That number is not divisible exactly by two.

Therefore it is going to be odd.

And that makes my whole number 27 odd.

So because this digit here in the ones column can not be divided exactly by two.

It makes the number an odd number.

So when we're looking for odd and even numbers, it's really important that we look only at the ones column because it is this digit that will help us to identify whether our whole number is odd or even.

For your independent task today, you are going to do exactly the same as you did for our new learning.

So you've been given 2-digit cards, this time five and three.

And I want you to make two to the two 2-digit numbers out of these digit cards.

Once you've made the two numbers that you can have those cards, I want you to have a go actually making them using your countable objects.

So you might have Dienes at home.

If not, you could use a number line like I showed you, or you might want to just draw out your Dienes, So your 10 sticks on your ones, but I would like you to make both numbers so that you can visually see them in a different representation.

Once you've done that, I want you to find which is the greatest number, which is the smallest number.

And I want you to identify whether each number is odd or whether it is even.

Once you've finished that first class.

There's a second one for you to do with the digit cards eight and one.

So you need to make the two 2-digit numbers that you can with those cards.

Then you need to make representations of them both, either on a number line or with Dienes or maybe in a Part-Whole Model.

And finally you need to find which number is the greatest, which number is the smallest and whether each number is odd or even.

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

Welcome back team, let's have a look at these answers then.

So for these two digit cards you could have made the number 53 or 35.

The greatest number out of both of these is 53.

And I know this because 53 has five tens, which has greater than three tens in 35.

This means, 35 is the smallest number.

Then you have to figure out if either number was odd or even 53 I know is odd because looking at my ones digit which is three, I cannot divide the number three exactly by two.

So therefore it is an odd number.

Same with the number 35.

Looking at my ones digit five, my number is going to be odd because five is not divisible by two.

The next two digit cards were eight and one, and the numbers you could have made with that were 81 or 18.

So the greatest number is 81.

And that's because it's got eight tens, which is much greater than the one ten 18 has.

So 18 is the smallest number.

81 is an odd number and that is because in the ones column, there is the digit one and one is not exactly divisible by two.

The digit eight, however, is even because I can divide eight by two and I'll get four.

So I know that 18 is going to be an even number because this ones digit is divisible exactly by two.

Now that you've completed your independent task guys, it is time for you to complete the quiz.

So when the video's ended, don't forget to give it a go and to recap everything that you've learned in today's lesson, That is the end of our lesson today team.

And I wanted to say a huge well done for your hard work today.

I thought you did a great job finding odd and even 2-digit numbers.

Hopefully I'll see you on another session soon.

Bye bye.

If you'd like to, please ask your parents or carer to share your work on Twitter, tagging @OakNational and #LearnwithOak.