Lesson video

Hello, my name's Mrs. Cornwell and I'm really pleased to be working with you today.

We're going to use some of the things you already know to help you with some new learning and I know you're going to do really well.

So let's go.

So in today's lesson, we're going to be learning how to count forwards and backwards in tens up to 50.

And this lesson comes from the unit counting in tens, decade numbers.

And by the end of today's lesson, you'll be able to recite the decade number names from zero to 50, going forwards and backwards and using the patterns in the count to help you.

And you'll also know what the term decade numbers means and how we use them.

So the words that are going to be important in today's lessons is going to be the number names, 10, 20, 30, 40, 50 and also the term decade numbers.

So in our lesson today, the first part of the lesson, we're going to look at counting forwards in steps of 10 to 50.

And then in the second part of the lesson, we'll count backwards in steps of 10 from 50.

In this lesson, you will meet Andeep and you will also meet Laura.

These numbers are the decade numbers, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100.

We use 'em to count when objects are in groups of 10.

So you can see these pencils are in packets of 10.

And instead of counting each pencil one by one, which would take a long time, we can use our decade numbers to count them in tens and count them more quickly.

And so we need to learn the pattern and the order of these decade numbers to help us to do that when we start counting larger groups of objects.

We're going to practise counting forwards in tens up to 50.

So we start our count at zero and we count zero, 10, 20, 30, 40, 50.

The order never changes.

So when you're counting forwards, you always count the numbers in the same order.

So let's practise counting forwards to 50 then, okay? It's important that we practise it because that's how you become better and better at it.

And then you know those numbers really, really well and you feel confident when you are using them.

So let's practise, first of all, counting in a loud voice.

Are you ready? Count with me.

Are you ready? 0, 10, 20, 30, 40, 50.

Well done.

Now let's practise in a quiet voice.

Are you ready? 0, 10, 20, 30, 40, 50.

Excellent.

Now let's try in a slow voice, slowly.

Are you ready? 0, 10, 20, 30, 40, 50.

Well done.

And then let's try quickly.

Okay, off we go.

0, 10, 20, 30, 40, 50.

That was much harder, wasn't it? Okay.

And then let's see if we can flash our 10 fingers as we count.

We won't flash them for zero, will we? Because zero means nothing.

So you wouldn't show any fingers for that.

But for our other decade numbers, because we've got 10 fingers, we'll use our 10 fingers to show that we've reached a decade number.

Are you ready? 0, 10, 20, 30, 40, 50.

Well done.

Excellent.

So we should be feeling more confident now because we've practised in lots of different ways.

I am counting in tens to 50.

Which number will come next? 0, 10, 20, 30.

That's right.

It will be 40, won't it? Well done.

Okay, and let's have another try.

0, 10, 20, 30, 40.

That's right.

After 40, it will be 50.

Well done.

Okay, time for you to have a try now.

So I'm counting forwards in tens.

What is the next number in my count? So 0, 10, 20.

What will come next do you think? So you've got three numbers that you can pick from.

Do you think it will be 30? Do you think it will be 13 or do you think it will be 50? Have a think about that, okay? Count the numbers and see which one you think would come next.

Did you get on? Let's count from the beginning to find out which one sounds right.

0, 10, 20.

That's right.

It should have been 30 next, shouldn't it? That's it.

Excellent.

We can see that 13 doesn't have that ty sound at the end like the other decade numbers.

10, 20, 30.

Okay, and 50.

We know that that one's not the next one after 20, is it? Well done.

So listen carefully, can you spot a mistake? <v Narrator>0, 20, 30, 40, 50.

</v> <v ->Did you spot it? That's right.

</v> When we count, we may miss a number, but we can correct ourselves, can't we? So that person there said 0, 20, 30, 40, 50, but we know it's 0, 10, 20, 30, 40, 50.

So they missed out the 10, didn't they? I'm sure if they counted again, they would correct themselves and put it right.

So let's listen carefully again.

Can you spot another mistake, a different mistake? <v Narrator>0, 10, 20, 13, 14, 15.

</v> <v ->Oh, did you spot it? That's right.

</v> They said some of the teen numbers instead of the decade numbers, didn't they? So they said 13, 14 instead of 30 and 40.

And we know the decade numbers end with that ty sound, don't they? Let's look at these two numbers, 15 and 50.

What's the same about them both and what's different? So if we look at them, they both start in the same way and that's why they can be quite easy to muddle up because it starts with fif, 15 and 50, so people can get them muddled because they only think about the start of the number.

So what's different then? That's right, it's the end of the number, isn't it? So we can see 15, it's a teen number and it has teen at the end, but 50 is a decade number and it ends in ty like our decade numbers.

A lot of our decade numbers end in ty, don't they? Most of them in fact.

So well done.

So counting tens to 50, saying the ty at the end of the word in a loud voice so we can really hear that they're decade numbers.

Are you ready? 0, 10, 20, 30, 40, 50.

Well done.

So let's count.

Can you spot a mistake when I count these numbers? 0, 10, 20, 40, 30, 50.

Hmm.

Look carefully at those numbers.

I'm going to give you a bit of thinking time.

See if you can spot a mistake there.

Did you spot it? Let's have a look.

0, 10, 20.

That's right.

Then it should have been 30, shouldn't it? Then 40, then 50.

Well done.

Okay, let's have a look at another group of numbers.

0, 10, 20, 13, 14, 15.

So I'll give you some thinking time again.

Okay, and let's count the numbers and see if we can spot the mistake.

0, 10, 20.

Ah, then it should have been 30, shouldn't it? And 40 and 50.

The decade numbers, not the teen numbers.

That's right.

Well done.

When we count forwards in tens, we can start from any decade number.

So we don't always have to start from zero or 10.

We can start from any of the decade numbers.

So count forward from these decade numbers.

30.

So we start our count at 30 and we count 30, 40, 50.

Well done.

Okay, and then let's try another one.

20.

We start our count at 20 and we count 20, 30, 40, 50.

Did you notice the order doesn't change, does it? You can start from a different starting point, a different number, but the order remains the same.

So here's another one for you to try on your own.

I'm counting forwards in tens, starting at different decade numbers.

Which correctly shows my count? So you're looking for the one that is in the correct order when we count our decade numbers in tens.

20, 13, 40.

30, 40, 50.

10, 20, 50.

Okay, so have a think and see which one you think is the correct order.

Okay, let's see how we got on.

Did you spot it? 30, 40, 50.

'Cause if we go back to the start and count from zero, that's the order we say them, isn't it? 0, 10, 20, 30, 40, 50.

You can see that top one has a teens number, 13, and that it doesn't look the same as a decade number and it doesn't sound the same either.

It doesn't have that 30 at the end of it, does it? It's a different sound.

And the bottom one, you can see 10, 20.

And then you know the number that comes after 20 when you count in tens is 30, not 50, isn't it? That's right.

Count forward from these decade numbers.

30.

So we start our count at 30 and we count 30, 40, 50.

And then here's another one.

We count from 20 this time.

We start our count at 20 and we count 20, 30, 40, 50.

Oh, there's Laura and she's saying, "You're not counting forwards because the numbers are written down the page.

Hmm, is she right? Is Laura right? Do we think we're still counting forwards? Let's have a look at those numbers.

20, 30, 40, 50.

We know we are counting forwards because the numbers are greater than the starting number.

So when the amount becomes bigger, the numbers become greater, then we're counting forward.

It doesn't matter which direction, you can go up or down and you can go across the page from either side.

But what's important when you're counting forwards is that the numbers become greater, the amount that they represent is more.

Look at decade numbers below.

We've got 10, 20, 30, 40, 50.

What do you notice about them all? That's right, they all end with the digit zero.

Find the decade numbers up to 50 on your 100 square.

That's right.

Did you spot it? The decade numbers are at the end of each line on your 100 square.

When we count in tens, we only count the decade numbers.

We miss a lot of numbers out, don't we? We skip the numbers in between and that's why it's called skip counting.

So when we count in tens, it's called skip counting because we miss some numbers out and we only say the decade numbers.

Put your finger on the number 10 and count up to 50 in tens with me.

Are you ready? So we start our count at 10 and we count 10, 20, 30, 40, 50.

And we can see we're counting forwards, aren't we? Because the numbers are becoming greater, but we're going down on our 100 square.

Can you point to the numbers that you skipped? Which ones did you miss out? That's right.

You missed all of the numbers on each line apart from the decade numbers, didn't you? They were the only numbers that we said on those top few lines.

As you know, we can start counting from different starting points.

Point to the number I say, then count forward in tens from that number to 50.

So we're going to start at 30.

We start our count at 30 and we count 30, 40, 50.

Well done.

Let's pick a different number.

10, so we start our count at 10 and we count 10, 20, 30, 40, 50.

I'm going to count forward in tens.

I'm going to start my count at 40.

What is the next number I will say? So you can put your finger on 40 there.

What number will I say next when I'm counting forward in tens? That's right, it will be 50, won't it? Well done.

I start my count at 20.

What is the next number I will say? So put your finger on 20 and then let's think what will the next number you count be? That's right, it's 30, isn't it? Okay, so now it's time for you to have a turn on your own again now.

Laura says she's counting forwards in tens.

Is she right? 0, 10, 20.

So is she counting forwards? Here's 100 square.

You can see those numbers.

The decade numbers 10, 20 on there.

Do you think she's counting forwards? Have a think.

Okay, so what did we think then? That's right, we know she is counting forwards because 10 is greater than zero and 20 is greater than 10.

Okay, and we know that when we're counting forwards that numbers become greater, don't they? The amount that they represent is more, and we know she's counting in tens because she's counting the decade numbers which end in zero.

Well done.

What is the next number she will say, do you think? So we've got 10, 20.

That's right, it will be 30, won't it? That becomes next when you're counting forwards in tens.

Well done.

So here's your task for the first part of the lesson.

Find the decade numbers up to 50 on your 100 square, okay? Then start at 10 and count up to 50.

So that's going to be the first part of your task, okay? And then after that, you are going to put your finger on 30 and think about what is the next number in your count, okay? And then you can start your count at 20 and you can count up to 50.

So pause the video while you have a try at that.

Let's see how you got on then.

So first of all, start at 10 and count up to 50.

So you put your finger on 10.

We start our count at 10 and we count 10, 20, 30, 40, 50.

Well done.

Right, then the next part was put your finger on 30.

What is the next number that you count? So put your finger on 30.

We start our count at 30.

What's the next number? We go 30, 40, that's right, well done.

And then start at 20 and count up to 50.

So we start our count at 20, 20, 30, 40, 50.

Excellent, well done.

You've worked really hard there.

So now we move on to the second part of today's lesson where we will be counting backwards in steps of 10 from 50.

So we can also count backwards in tens from 50.

We start our count at 50 and we count 50, 40, 30, 20, 10, 0.

The order never changes, does it? When we count backwards, the order always stays the same.

Count backward from 50 in 10.

So we're going to practise again, aren't we? Because that's how we get better and we feel more confident when we practise in lots of different ways.

So we're going to practise in a loud voice first of all.

So are you ready? So 50, 40, 30, 20, 10, 0.

Well done.

Now let's practise in a quiet voice.

50, 40, 30, 20, 10, 0.

Well done.

Now let's practise doing it slowly.

50, 40, 30, 20, 10, 0.

Well done.

And then let's do it quickly.

Are you ready? 50, 40, 30, 20, 10, 0.

Excellent.

Now we're going to try counting backwards, flashing your 10 fingers as you count.

Remember, when you say zero, you won't need to show any fingers because zero means nothing, doesn't it? Are you ready? 50, 40, 30, 20, 10, 0.

Well done.

That was excellent.

So here we are then.

I'm counting backwards in tens.

What is the next number I will say? So we've got 50, 40, 30.

That's right.

It was 20, wasn't it? Excellent.

Let's try another one then.

50, 40, 30, 20.

What will it be this time? That's right, it will be 10, won't it? Okay, and then 50, 40.

That's right, it will be 50, 40, 30, won't it? And that's 30 for us to see.

Okay, so another time for you to have a try on your own.

I'm counting backwards in tens.

What is the next number I will say? So we've got 50, 40, 30, and you've got to think about what that next number is.

So you can pick, you may think it's 40, you might think it's 10 or you might think it's 20.

So have a think now.

Okay, I'll give you a bit of time to think about that.

Say those numbers and think which is the next number you will say.

Okay, how did we get on? Let's start from 50 and count backwards and see which one sounds right.

50, 40, 30.

That's right, it will be 20 that comes next, wouldn't it? Excellent.

Well done 'cause we know that order stays the same.

It never changes, does it? So now let's count backwards in tens from 50 and say the numbers that are missing.

50, 40, 30, 20, 10.

Which number did you think was missing? Let's start from 50 again and count back.

50, 40, 30, 20, 10, 0.

That's right.

Let's try another group of numbers then.

Are you ready? Starting at 50 again.

50, 40, 30, 20.

What's missing now? So let's try.

50, 40, 30, 20, 10, 0.

Well done.

Okay, and then let's start again.

See which numbers are missing this time? 50, 40, 30.

Okay, what numbers do we think are missing there? I nearly told you then, didn't I? Let's try.

50, 40, 30, 20, 10, 0.

Well done.

Excellent.

You're getting better every time you count.

So here's one for you to practise on your own now here.

So we've got count backwards in tens from 50 and say the numbers that are missing.

So we've got 40, 30, hmm, hmm.

Hmm, so three missing numbers time, 40, 30.

Have a think about that and see which numbers you think you'll say next when you're counting backwards.

Are you ready? So 40, 30, 20, 10, 0.

Well done.

Excellent.

So here we are then.

I'm counting backwards in tens.

What is the next number I will say? So we've got 50, 40, 30.

That's right.

It was 20, wasn't it? Excellent.

Let's try another one then.

50, 40, 30, 20.

What will it be this time? That's right, it will be 10, won't it? Okay, and then 50, 40.

That's right, it will be 50, 40, 30, won't it? And there's 30 for us to see.

Okay, so another time for you to have a try on your own.

I'm counting backwards in tens.

What is the next number I will say? So we've got 50, 40, 30, and you've got to think about what that next number is.

So you can pick, you may think it's 40, you might think it's 10 or you might think it's 20.

So have a think now.

Okay, I'll give you a bit of time to think about that.

Say those numbers and think which is the next number you will say.

Okay, how did we get on? Let's start from 50 and count backwards and see which one sounds right.

50, 40, 30.

That's right.

It will be 20 that comes next, wouldn't it? Excellent.

Well done.

'Cause we know that order stays the same.

It never changes, does it? Listen carefully.

Can you spot the mistake here then? So listen carefully as I count.

So we're starting at 50, I start my count at 50, 50, 40, 30, 40, 50.

What do we think about that? There's Laura.

She says, "This doesn't sound right.

I wonder what mistake I made." Can you spot the mistake? That's right.

50, 40, 30, 40, 50 isn't right.

It should be 50, 40, 30, 20, 10, shouldn't it? That's right.

Laura mixed the order of the numbers up.

Remember, the order never changes.

They always go in the same order, don't they when you're counting backwards.

I'm counting backwards in tens from 50.

What mistake did I make here? So here's one for you to try on your own, okay? So let's have a look.

50, 40, 13, 20, 10, 0.

Can you spot the mistake? Have a look, I'll give you a bit of thinking time.

See if you can find out where the mistake is.

Okay, did you spot it? 50, 40, 30 it should have been, not 13, shouldn't it? All of the decade numbers have that zero.

And they also have that ty sound at the end.

So 50, 40, 30, 20, 10, 0.

Well done.

When we count backwards from 50 in tens, we can start from any decade number.

So we don't always have to start from 50, do we? So count backwards from these decade numbers.

30, 20, 10, 0.

Okay, and let's try another set.

20, 10, 0.

50, 40, 30, 20, 10, 0.

So here's one for you to try on your own.

I'm counting backwards in tens from different starting points.

Which of these is correct? So 40, 30, 40, 10, 20, 30, 30, 20, 10.

Which one do you think is correct when you're counting backwards? I'll give you a bit of thinking time.

That's right.

Did you spot it? 30, 20, 10 when we count backwards is the correct order, isn't it? We can see the top one has two 40s and we know that you don't say the same number twice when you're counting backwards in tens, the order always stays the same.

And we can see that the middle one, you started at 10 and then you've gone 20, 30.

So we've counted the direction is backwards, isn't it? But actually, the numbers are getting greater.

So actually, that's not going backwards, is it? Well done.

Okay, count backwards in tens from these decade numbers then.

So we've got 30 there, haven't we? 30, 20, 10.

Okay.

And then let's have a look at another set.

50, 40, 30, 20.

Ooh, and there's Laura.

She says, "You're not counting backwards because the numbers are being written up the page." Do we think she's right? Do we think we are counting backwards? That's right, we know we are counting backwards because the numbers are becoming less each time, aren't they? They're worth less.

They they represent a smaller amount.

So it doesn't matter where you start.

If the numbers become less, then we know that we're counting backwards.

Okay, so look at these two groups of numbers.

We've got two groups there, and I want you to think about what's the same about them both.

What do you notice? That's right.

They all end in a zero, don't they? And we know that they're all decade numbers because they end in a zero.

Okay, what's different about them all? That's right, the number that is before the zero or next to the zero is different in each case because that tells us which decade number it is, doesn't it? Laura says, "Are we counting forwards or backwards?" What do you think? It depends where you start counting, doesn't it? So with this first group here, if I start at 50 at the top and I say 50, 40, 30, 20, 10, 0, I'm counting backwards because the numbers are becoming less.

But if I start at the bottom at zero and say 0, 10, 20, 30, 40, 50, then I'm counting forwards, aren't I? Because the numbers are becoming greater.

So it depends where you start counting, doesn't it? If the numbers you count are greater than the starting number, we're counting forwards.

If the numbers are less than the starting number, we are counting backwards.

Let's have a try on your own then.

Look at these numbers.

So there's a group of numbers, use them to count forwards.

Where will you start counting? Have a think about that.

I'll give you a bit of thinking time and see if you can count those numbers forwards.

Okay, so where did you start counting? Did you start at zero 'cause that's the smallest amount, isn't it? And then the numbers get greater from there.

0, 10, 20, 30, 40, 50.

That's when you're counting forwards.

Now, can you use 'em to count backwards? Think about where you will have to start now.

Okay, so where did you start counting this time? That's right.

50 is the greatest amount, isn't it? And we know the numbers have to become less.

So we start at 50 and we count, don't we? 50, 40, 30, 20, 10, 0.

Now we know that the numbers have become less.

So we're counting backwards.

So find the decade numbers up to 50 on your 100 square.

We know that they're at the end of the line, don't we? Put your finger on 50, on your 100 square and then count backwards in tens with me from that number down to 10.

Are you ready? So put your finger on 50.

I start my count at 50 and I count 50, 40, 30, 20, 10.

And then you could say zero, couldn't you? You can't see it on the 100 square, but we know it means nothing.

It's there isn't it? We can start counting from any decade number, can't we? So count backwards in tens from each number with me.

30.

So let's count from 30.

We start our count at 30 and we count 30, 20, 10.

And then you could say zero.

We can't see it on the 100 square, can we? But we know that if we count back in tens, the number that you say after 10 is going to be zero.

Let's count backwards from 40, 40, 30, 20, 10.

And then it will be zero, wouldn't it? Count backwards in tens from 40 on your 100 square and let's think about the next number that we say this time.

So we're gonna start at 40.

What will be the next number you say counting backwards? That's right.

It will be 30, won't it? So here's another task for you to do on your own.

Find the decade numbers up to 50 on your 100 square, start at 50 and count back to 10.

I'll give you a bit of time to do that.

Okay, and now put your finger on 40.

What is the next number you will count? And then start at 30 and count back to zero.

Okay, let's see how we did then.

So start at 50 and count back to 10.

There's 50, 50, 40, 30, 20, 10, 0.

Well done.

Okay, put your finger on 40.

What will be the next number that you count? That's right, it will be 30 and start at 30 and count back to 0, 30, 20, 10, 0.

Well done.

So here is your task for the second part of today's lesson then.

So sit in a circle in small groups or try with a partner.

You might work with one other person.

Count backwards from 50, taking it in turns to say the number until you reach zero.

So we've got Andeep here and he says, "I am the first person to count.

I start at 50 and I can choose how we will say the numbers.

I choose a squeaky voice." And then repeat when you've got all the way around, taking it in turns to zero and reach zero, then repeat with a different person starting.

When you become confident, try counting round the circle in your thinking voice, imagining the numbers.

Can you predict who will say the number zero? So pause the video while you have a try at that now.

Okay, and here's a group.

We've got a group here of children and they're going to show us how they did it.

So here's Andeep, and he says, "I'm the first person, I say 50.

I choose that we must all continue the count in a squeaky voice." And then we're going to go through and each child will take a turn.

So Andeep starts and he'll say, 50, 40, 30, 20, 10, 0.

And now they've got to zero.

So then the next person has to start with 50 and choose a different way to count.

There's Izzy and she says, "ow it's my turn to go first and choose how to say the numbers.

I will start my count at 50 again." Well done.

Is that what you did? Excellent.

You've worked really hard today, haven't you? So let's have a think about what we've learned in today's lesson when we've learned to count forwards and backwards tens to 50.

So we found out that decade numbers are used when counting forwards and backwards in tens.

You can count tens from any decade number.

You don't always have to start from the same number.

And we know that the order always stays the same, don't we? And a 100 square can be used to help you count the decade numbers.

We know now, don't we, where the decade numbers are on a 100 square and we can use that to help us to count forwards and backwards.

So well done.

You've worked really hard this lesson and you've found out lots about counting forwards and backwards in our decade numbers, which you'll be able to use in some of the lessons that you do later on in your learning.

So well done.

Excellent.