Lesson video

Hello, I'm Mrs. Cayley and I'm really excited to help you with your maths today.

So in today's lesson, we're going to explore odd and even numbers up to 20.

So let's have a look at today's lesson outcome.

Here's the outcome of today's lesson.

I can explore odd and even numbers within 20.

So we'll be looking at odd and even numbers all the way up to 20.

Here are the key words for today's lesson.

We've got three key words today.

Can you repeat them after me? My turn, pair.

Your turn.

My turn, odd.

Your turn.

My turn, even.

Your turn.

Well done.

You might have seen these words before.

Look out for them in today's lesson.

Here's today's lesson outline.

We'll be exploring odd and even numbers within 20.

We'll start off by looking at odd and even numbers and then we'll look at odd and even numbers on a number line.

So let's start with the learning.

Here are some children that are going to help us today.

We've got Sophia and Jun.

Sophia and Jun have made some numbers out of cubes.

These are some even numbers.

Can you see? They've made two, four, six and eight out of cubes.

I wonder what makes these numbers even? They have pairs of cubes.

Pairs means things that come in groups of two.

We've got a stem sentence to help us here.

Is made of pairs.

It is an even number.

So let's have a look at the number two.

Has it been made of pairs? How many pairs has it been made of? Here I've put a box around a pair.

We've got one pair, haven't we? Can you say the stem sentence with me? Two is made of one pair.

It is an even number.

Let's have a look at the number four.

I wonder how many pairs it's been made of.

I've put a box around the pairs.

Can you say the stem sentence with me? Four is made of two pairs.

It is an even number.

Let's look at the number six.

How many pairs has it got? It's got three pairs, hasn't it? Can you say the stem sentence with me? Six is made of three pairs.

It is an even number.

Let's move on to the number eight.

How many pairs has it got? Let's say the stem sentence together.

Eight is made of four pairs.

It is an even number.

Jun said, "These shapes have flat tops." Can you see? Because of the pears, they've all got a flat top.

Sophia said, "These shapes have groups of two." So they've got pairs, haven't they? Jun said, "These shapes have pairs of cubes." These numbers are called even numbers.

What do you notice here? We've got the number eight and the number nine.

What's the same and what is different? Jun said, "Eight has four pairs of cubes." Here are the four pairs of cubes.

Has nine got pairs of cubes? Sophia said, "Nine has four pairs of cubes and an extra cube." Can you see the extra cube at the top? So eight is an even number and nine is not an even number.

It's an odd number.

These are some odd numbers.

Can you see Jun and Sophia have made the numbers one, three, five, seven and nine? They look a bit different to the even numbers, don't they? They have an extra cube.

So these numbers are not made of pairs.

Here's a stem sentence to help us.

Is not made of pairs.

It is an odd number.

Let's see if you can say the stem sentence with me.

We'll use the first number, one.

One is not made of pairs.

It is an odd number.

Let's try it with the number three.

Three is not made of pairs.

It is an odd number.

Let's try it with the next one.

Five is not made of pairs.

It is an odd number.

Let's move on to the next one.

Seven is not made of pairs.

It is an odd number.

And finally, nine is not made of pairs.

It is an odd number.

Jun has noticed that these shapes do not have flat tops.

They have an odd block, so they've got an extra cube at the top.

Sophia said, "These shapes do not have groups of two." Jun said, "These shapes do not have pairs of cubes." These numbers are called odd numbers.

Sophia and Jun are making numbers from 10.

Here's the number 10, they've used counters on a 10 frame.

Here we've got 11, 12, 13, 14 and 15.

What do you notice about those numbers? Can you see some of them are made of pairs of counters and some of them have got an extra counter? So some are even and some are odd.

Jun and Sophia are going to carry on with the pattern.

What do you notice? We've got 16, 17, 18, 19, and 20.

Can you see some of them have got pairs of counters and some of them have got an extra one? Sophia said, "Some shapes have flat tops." Jun said, "Some shapes have groups of two." Some shapes have pairs of dots.

So which ones have got groups of two or pairs of dots? Can you point to the ones that have got pairs? We've got 16, 18 and 20.

They've got pairs of dots, haven't they, and a flat top.

So they're the even numbers.

Jun said, "Some numbers are odd and some are even." Which ones are the odd numbers? They've got an extra counter.

That's right, it's 17 and 19.

They're the odd numbers.

Is 10 an even or odd number? Has it got pairs of dots or has it got an extra one? I can see some pairs, can you? There's one pair, two pairs, three pairs, four pairs, five pairs of counters here.

So 10 can be made of groups of two.

This shape has a flat top.

It is an even number.

Let's say the stem sentence together.

10 is even, because it can be made from groups of two.

We could put odd or even numbers on top of this flat top.

Can you imagine some other numbers going on top of the 10? Here we've got some more counters on top of 10.

This is 11.

Is 11 an even or odd number? Has it got pairs of dots? Jun said, "11 cannot be made of groups of two." Sophia said, "This shape has not got a flat top." It is an odd number.

Do you agree? Jun said, "11 is one 10 and one one." Here we can see it on a put-put hole model.

Can you see, 11 is being partitioned into tens and ones? It's got one 10 and one one.

We know that 10 is an even number.

I can see on the 10 frame that 10 is an even number.

It's got pairs of dots.

We know 10 is even, so we just need to look at the ones.

So if we look at the 10 frame, can you see the ones above the 10? There's just one one, isn't there? And this is an odd number.

So on the 10 frame, I can see that on top of the 10, which has got a flat top, we've got an odd number.

Sophia said, "The ones digit is an odd number." Here we've got the stem sentence to help us.

Is odd, because the ones digit is odd.

Can you say it with me? 11 is odd, because the ones digit is odd.

Jun and Sophia have made a different number.

They've made the number 14.

Is 14 an odd or even number? Jun said, "14 is one 10 and four ones." So here it is on a put-put hole model.

Can you see 14 has been partitioned into its tens and ones? It's been partitioned into 10 and four.

Sophia said, "We know 10 is even." 10 is an even number.

It's been made of pairs.

I can see on the 10 frame that 10 is an even number.

So we can just check the extra ones.

Can you see the extra ones on top of the number 10 on the 10 frame? Is it an odd or an even number? Can it be made from pairs? Sophia said, "Four is even, because it can be made of pairs." There's one pair and there's another pair.

So four is an even number.

So 14 must be even.

Here we've got a stem sentence to help us.

Is even, because the ones digit is even.

Can you say it with me? So we've got 14 is even, because the ones digit is even.

So it doesn't matter about the tens digit, we knew that that was even.

We just needed to look at the ones digit.

Let's check your understanding.

Is 19 an odd or even number? Can you look at the picture and the put-put hole model and decide whether 19 is an odd number or an even number and say the stem sentence? So the stem sentence says, "19 is because the ones digit is." So pause the video and have a think about this one.

What did you think about the number 19? So I can see that the number 19 has been partitioned into 10 and nine.

10 is an even number and nine is an odd number.

Let's have a go at saying the stem sentence.

We know that 10 is even, so we only need to look at the ones.

Let's say the stem sentence together.

19 is odd, because the ones digit is odd.

Is that what you thought? We can find larger odd and even numbers, so we can go even higher than 20.

Here we've got 10 counters.

Is 10 an odd or an even number? 10 is an even number.

Now we've got 10 and another 10, that's 20.

20 is an even number as well.

Can you see that's also made of pairs? Now we've got another 10, so we've got 30.

30 is an even number as well.

It's also got pairs.

Now we've got 40.

40 is an even number two, it's also got pairs.

Now we've got 50 counters.

50 is an even number as well.

They're all even numbers, because they've got pairs of counters.

These are all even numbers.

Each group of 10 is even.

Any number that ends in a zero is an even number.

10 is an even number.

So any group of 10 will be even.

Sophia and Jun have made a larger number here.

They've made the number 25.

Is 25 an even or an odd number? Jun said, "25 is two tens and five ones." Can you see the two tens at the bottom there and the five ones on top? We know that 20 is even.

So those two tens at the bottom there which make 20, they're even.

So we only need to look at the ones.

We've got five ones.

Is five an even or an odd number? Five is odd, it cannot be made of pairs.

We've got one pair, another pair, but we've got an extra counter.

So five is an odd number.

20 is even, but five is odd, so 25 is odd.

The ones digit is odd.

Should we say the stem sentence together? 25 is odd, because the ones digit is odd.

Jun and Sophia have made another number here.

They've made the number 34.

Is 34 an even or odd number? Jun said, "34 is three tens and four ones." So here it is on the put-put hole model.

34 has been partitioned into 30 and four.

We know 30 is even.

I can see on the 10 frames that 30 is an even number.

It's three lots of 10, isn't it? So we only need to look at the ones.

We've got four ones.

Four is even, it can be made of pairs.

We've got two pairs there, so four is an even number.

So what about the number 34? Is it even or odd? 30 is even and four is even.

So 34 is even.

The one's digit is even.

Should we say our stem sentence together? 34 is even, because the one's digit is even.

Any number that ends in zero is an even number.

They're the tens numbers, aren't they? All tens numbers are even numbers.

To find if a number is odd or even, we only need to look at the ones digit.

So here we've got the number 13 and 14 and we only need to look at the ones digit, because we know that the tens digit is even already.

So with 13, three is an odd number.

So 13 is an odd number.

And with 14, four is an even number.

So 14 is an even number.

Let's check your understanding.

Who is correct? Here we've got the number 18.

It's been made of one 10 and eight ones.

Jun said, "I think 18 is odd, because one is odd." Sophia said, "I think 18 is even, because eight is even." Pause the video and think about who is correct.

So we only need to look at the ones digit, don't we? Eight is an even number.

So Sophia is correct.

18 is an even number.

Here's a task for you to have a go at.

Can you hide some one to nine number shapes in a bag and pull one out to go with the 10 shape to make a teen number? Decide if your number is odd or even and you can use the stem sentence at the bottom to help you decide.

Is odd or even, because the ones digit is odd or even.

So see if you can find some number shapes or cut some out or make some out of cubes and have a go at this game.

Here's the second part of your task.

Now try the game with number cards.

Pick a one to nine card to put in the ones column of the place value chart to make a teen number.

Decide if your number is odd or even.

So we've got the number cards from one to nine and you're going to put it onto the place value chart.

We've already got one 10 there, so it will make a teen number.

And then decide if your number is odd or even.

And say the stem sentence, is odd or even, because the ones digit is odd or even.

Here's the next part of your task.

Can you sort the numbers into odd or even and add your own? So here we've got some teen numbers, 11, 12, 13, 14 and 15.

Can you decide whether they are odd or even numbers and put them in the right place on the table? And have a go at saying the stem sentence as well.

Is odd, because the one's digit is odd or is even, because the one's digit is even.

And try to add some of your own numbers as well.

So pause the video and have a go at your tasks.

How did you get on with your tasks? Did you play the game? You might have tried pulling out the number three and putting it there with the number 10.

So that makes the number 13.

Jun said, "One 10 and three ones is 13." Three is odd.

Sophia said, "13 is an odd number, because the ones digit is odd." Or you might have tried an even number.

Here we've got the number six, which when you put it with the number 10 becomes 16.

Jun said, "One 10 and six ones is 16, six is even." Sophia said, "16 is an even number, because the ones digit is even." How did you get on with the second part of your task? You might have tried pulling out the number one to go with 10.

This makes 11.

11 is odd, because the one's digit is odd.

Or you might have made the number 15.

15 is odd, because the one's digit is odd or you might have made some even numbers like this one.

18, 18 is even, because the one's digit is even.

How did you get on on the last part of your task? Did you sort the numbers into odd or even and add your own? So here we've got some odd numbers.

11, 13, 15, 17 and 19 and we've got some even numbers, 10, 12, 14, 16 and 18.

Let's have a go at the stem sentence.

So you might have chosen the number 11.

11 is odd, because the one's digit is odd or you might have chosen the number 14.

14 is even, because the one's digit is even.

Can you say the stem sentences for your numbers? Let's move on to the second part of the lesson.

We'll be looking at odd and even numbers on a number line.

Here's a number line.

What do you notice? Two, four, six, eight, and 10.

Jun said, "These all have pairs, so they are even.

We are going up by two each time." Sophia said, "We are saying even numbers." What do you notice this time? One, three, five, seven and nine.

Jun said, "These do not have pairs, so they are odd.

We are still going up by two each time." Sophia said, "We are saying odd numbers." Jun is skip counting the even numbers on a number line.

Can you see the even numbers there on the number line? Let's count forward in twos.

Two, four, six, eight, 10, 12, 14, 16, 18 and 20.

Did you notice a pattern? So here we've got the numbers two, four, six, eight and 10.

And here we've also got the numbers two, four, six, eight and 10.

They've been added on to another 10.

When we skip count in twos from zero, we say the even numbers.

The ones digit follows the pattern, two, four, six, eight and zero.

Let's start at one and count in twos.

So see if you can see the number one on the number line and we're going to skip count in twos.

So say it with me.

One, three, five, seven, nine, 11, 13, 15, 17, 19.

Jun said, "We are skip counting." Sophia said, "Can you see the jumps of two?" When we skip count in twos from one, all the numbers are odd.

So can you see at the bottom there, I've put a purple circle around all the odd numbers? This time, let's start at zero and count in twos.

Can you do it with me? Zero, two, four, six, eight, 10, 12, 14, 16, 18, 20.

Jun said, "We are skip counting." Sophia said, "Can you see the jumps of two?" When we skip count in twos from zero, all the numbers after zero are even.

Can you see I've put a green circle around all the even numbers at the bottom there? So the numbers alternate from odd to even.

Odd, even, odd, even, odd, even, odd and so on.

Jun is wondering if the pattern carries on.

Here we've got some bigger numbers on the number line.

Does the pattern carry on? Let's try skip counting in twos from 20.

20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40.

Jun said, "We can carry on skip counting." And we could go even higher, couldn't we? Sophia said, "We can find larger even numbers." When we skip count in twos from zero, all the numbers after zero are even.

Jun is wondering if the pattern carries on for odd numbers.

So we're going to start at 21 and skip count in twos.

Can you do it with me? 21, 23, 25, 27, 29, 31, 33, 35, 37, 39.

Jun said, "We can carry on skip counting." Sophia said, "We can find larger odd numbers." So we could keep going even higher.

When we skip count in twos from one, all the numbers are odd.

What do you notice here? We've got a number line from zero to 10 and from 10 to 20.

Look at the numbers that I've put a purple circle round.

What do you notice about them? We've got one, three, five, seven, nine, 11, 13, 15, 17, 19.

Jun said, "These are all odd numbers." Sophia said, "We can use the single digit numbers to help." Can you see something that's the same about the single digit numbers along the top number line and the two digit numbers, the teen numbers, on the bottom line? Yes, they do end in the same numbers, don't they? So odd numbers end in one, three, five, seven or nine.

So the ones digit is always one, three, five, seven or nine.

What do you notice here? Have a look at these two number lines.

The first number line goes from zero to 10 and the second number line goes from 10 to 20.

What numbers have I put a green circle around? Jun said, "These are all even numbers." So we've got two, four, six, eight, 10, 12, 14, 16, 18 and 20.

What do you notice about those numbers? Sophia said, "We can use the single digit numbers to help." Can you see that they all end in two, four, six, eight or zero? Because even numbers end in two, four, six, eight or zero.

Let's check your understanding.

Who is correct? Jun said, "Four is an even number, so 14 will be even." Sophia said, "14 is an odd number, because one is odd." Pause the video and think about who you agree with.

Jun was correct.

Four is an even number, so 14 will be even, because we are looking at the ones digit, aren't we? Even numbers end in two, four, six, eight or zero.

Here's a task for you to have a go at.

Can you pick a number and say whether it is odd or even? We've got the numbers from 11 up to 20 here and can you decide whether they are odd or even? You could use the stem sentence to help you.

Is odd or even, because the ones digit is odd or even.

When you've decided whether they're odd or even, now, can you put the numbers on a number line? Can you use what you know about odd and even numbers to say where it goes? So pause the video and have a go at your task.

How did you get on with your task? Did you put the numbers on the number line? Here, I've put the numbers between 10 and 20 on the number line.

So it goes 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 and 20.

Can you see that I've put a purple circle round the odd numbers and a green circle round the even numbers? Did you use the stem sentence to help you? So you might have chosen the number 11 for example.

11 is an odd number, because the ones digit is odd.

Or you might have chosen an even number like 14.

14 is an even number, because the ones digit is an even number.

Is that what you found? Well done, everyone, we've got to the end of our lesson.

Today, we were exploring odd and even numbers within 20 and this is what we found out.

Numbers are odd or even.

All tens numbers are even.

To find if a number is odd or even, we only need to look at the ones digit.

A number is even if the ones digit is even and a number is odd if the ones digit is odd.

And remember that this works for any number, even really big numbers.

Well done, everyone.

See you soon.