Lesson video

Hello, my name's Mrs. Cornwell and I'm going to be helping you with your learning today.

Now, today we're going to be finding out all about two digit numbers.

We're going to be looking very carefully, thinking about what we notice, looking for any patterns that can help us so we can use things that we already know to help us with new learning.

So I'm really looking forward to working with you today.

I know you're going to work really hard and will do really well, so let's get started.

So, our lesson today is called "Count Groups of Tens and Extra Ones," and it comes from the unit "Counting and Representing the Numbers From 20 to 99." So in our lesson we're going to learn how to count larger groups more efficiently by grouping the objects into tens and then counting the groups of 10 and the extra ones.

So by the end of today's lesson, you should feel much more confident with counting larger groups of objects.

So our keywords today, there's only one and it is "digit." So my turn, digit.

Your turn.

Well done.

So the first part of our lesson is called "Making Groups of Tens and Ones." And in this lesson you will meet Andeep and also Laura.

Laura is counting the straws and here she is.

Look, she's counting them in ones, isn't she? And she says, "I keep losing count." "I wonder if there is a more efficient way to count them?" says Andeep.

"I could put them into a group of 10," says Laura.

And there we are.

She's put them into one bundle of 10 straws, hasn't she? This is one one.

This is 10 ones.

It is also one 10.

And so you can put it together into one 10 and then it makes larger groups easier to count.

10 ones are equal to one 10.

Andeep is counting the pencils.

"I counted up to 35, but I kept losing count,' he says.

"I wonder how I could count them more efficiently?" Hmm, what do you think? "You could group them in 10," says Laura.

"That would be easier than counting them in ones, wouldn't it?" So we can see there's one group of 10, two groups of 10, three groups of 10 and some extra ones.

There are three groups of 10 and that's right, five extra ones.

Does Andeep still have 35 pencils? Yes he does, doesn't he? If he counted them again in ones there would still be 35 ones.

We can represent the tens and ones on a Gattegno chart.

So here we are.

So how many tens have we got? We've got three tens, which we know is the same as 30 and then we have got five extra ones.

So it would be 30 and five.

There are three tens and five extra ones.

"I wonder how many pencils there would be if we counted them again in ones," says Laura.

Hmm, how many do you think? That's right, we would still have 35 ones, wouldn't we, if you split the tens into ones because we know one 10 is the same as 10 ones.

Use some objects around the room to group objects into tens.

And then Andeep's saying, "I use pegs on some ten frames," and there they are, look.

So, he's got four groups of 10 and then some extra ones there.

"I made cubes into sticks of 10," says Laura.

And there we can see she's got some groups of 10 and some extra ones.

"Let's count the groups of 10 Andeep has.

So, I have Mm groups of 10 and Mm extra ones.

What do we think? Count your groups of 10.

So we've got 1, 2, 3, 4 groups of 10.

How many extra ones have we got left over? 1, 2, 3, 4, 5, 6.

Six extra ones.

Show me one 10.

So what will Andeep show Laura? That's right, we'll show one group of 10.

Show me 10 ones.

That's right, so you could split your one group of 10 into 10 ones, couldn't you? Show me 10.

So which will Andeep show Laura? Oh, so he could show one group of 10, couldn't he? That's 10.

But he could also show 10 ones.

That's also 10 isn't it? They're worth the same amount.

10 ones are equal to one 10.

And if we counted all the pegs in ones again, how many do you think we'd have? That's right, there would be 46 ones.

We can find the total by counting in ones or by counting the groups of 10 and the extra ones can't we? Laura is counting the straws and uses digits to record the numbers and we can see that she's used a place value chart, hasn't she, to record that there are seven tens and five extra ones.

"I think this number has 75 ones," says Andeep.

"I think this number only has five ones." says Laura.

Who is right, do you think? Hmm, I wonder.

Andeep is right.

There are still 75 ones but some have been grouped into tens.

So we can only show the extra ones on the place value chart.

Okay, so now it's time to check your understanding.

Use the stem sentences to describe Laura's cubes.

There are Mm groups of 10 and Mm extra ones.

There are Mm ones.

Okay, so pause the video now while you try that.

Okay, and let's see how you got on then.

So there are five groups of 10 and five extra ones.

That's right.

And how many ones will there be altogether, if we took the groups of 10 apart and put them in, counted them in ones.

That's right, there would be 55 ones wouldn't there? Laura has lots of pens on the table.

She counts them in ones but keeps losing count.

Let's see how she could count them more efficiently.

What could she do, do you think? "I have an idea you could group them in tens," say Andeep.

So there's one group of 10, two groups of 10, three groups of 10, four groups of 10.

Now I can count them more efficiently.

So there are 1, 2, 3, 4 tens and then we can see there are four extra ones.

We know if we counted them in ones there would still be 44 ones wouldn't there? So we know there would be 44 ones.

Let's see how we can represent this on a place value chart.

So how many groups of 10 would we have? We have four groups of 10 and four more ones.

So four groups of 10 and four extra ones there.

The four shows we have four groups of 10.

And the other four shows we have four extra ones.

We know four tens, four is the same as 44, don't we? There are 44 ones.

Okay, so now it's time to check your understanding again.

Use the place value chart to complete the stem sentences.

Pause the video now while you try that.

And let's see how you did.

So how many groups of 10 have we got? That's right, we have eight groups of 10 and three more ones.

And if we counted them in ones we would have- That's right, 83 ones.

Well done if you did that.

So here's this task for the first part of our lesson then.

Play a matching game with the cards, sort the cards into three piles, words, numerals or picture and turn over two to see if they match.

So pause the video now while you try that.

So let's see how you got on.

Did you match these? That's 45, isn't it, 45 ones? Or you could have matched it with four tens and five ones.

And then we can see the pens are in groups of 10 and we've got two extra ones.

So it will be 32 or three tens and two ones.

And then the pizzas? How many groups of 10 have we got and how many will that be? We can count them in tens and then count on in ones.

So it'll be 94 or nine tens and four ones.

And then lastly, 23 or two tens and three ones.

And then there's the answers for the other cards that you had as well.

So well done if you did that.

Now the second part of our lesson is called "Reading and Recording Groups of Tens and Ones." So we know multiples of 10 are made up of some tens and no ones.

So we can see there 60, it's six tens, isn't it? The "ty" at the end of the word represents tens.

This number has six tens and no ones.

And there that's what it looks like on a place value chart.

We can see the six represents six tens and the zero represents zero ones.

We write 60 and we say sixty.

Andeep adds seven more pencils and there they are, look.

"We still have six tens," he says, "but we have seven extra ones." What number is this? Hmm, I wonder, let's check.

There are 1, 2, 3, 4, 5, 6, tens and seven more ones.

"I will think of my Gattegno chart," says Andeep.

Oh, so if you think about six tens and seven more ones, you can easily see the number.

So we know that it is six tens, seven, or 67, don't we? And that's how you write it.

60 represents six tens and seven represents seven ones.

Let's use digits to write the number 67 and we can write them in our place value chart, can't we? We write the six, there we go.

This represents the six tens, 60.

Then we write the seven.

This represents the seven extra ones, doesn't it? Point to each digit as you say it.

67, sixty-seven.

How many tens does this number have? We know 60 means six tens, don't we? So the 60 is six tens.

How many extra ones does it have? That's right, it has two extra ones doesn't it? Six tens and two ones in 62.

There are six tens and two ones.

This number is 62.

If I check by counting in ones, how many ones would there be? There would still be 62.

That's right, well done if you noticed that.

Let's use the digits to write the number 62.

We write the six.

This represents the six tens, 60.

Then we write the two.

And what does that represent I wonder? That's right, it represents the two extra ones, 62.

Point to each digit as you say the number.

62, sixty-two.

Okay, so now it's time to check your understanding again.

Select the correct number to represent the picture.

Now I'm not going to read these numbers to you because we're going to see if you can read the numbers, but have a look at the picture to help you and think about what each part of the picture represents.

So pause the video now while you try that.

So how did you get on? So if we have a look at the number under the picture there, we can see that it says 30 and then we have to pick either 33, 34 or 35, don't we? So we have a look.

The 30 represents a three tens in the picture, doesn't it? And then we have five extra ones.

So it will be 35, won't it? So well done if you noticed that.

The 30 represents the three tens and the five represents the five ones.

So it's three tens, five or 35.

Well done if you got that.

So now, Andeep is counting the stickers he has in his book.

Oh, he's got a lot of stickers there, hasn't he? He must have been working really hard.

Let's see how many he has.

So 10, 20, 30, 40, 50.

So he's counted them in tens, hasn't he? Andeep writes the number in his place value chart.

There, so he had 50 stars there didn't he? And then six extra ones.

What mistake has been made? Do you notice anything? Look carefully at that place value chart and think about your dual counting to help you with that.

Hmm, how would we say the number of stars that Andeep has from dual counting? That's right, there are 50 ones that- but there are five tens.

So we would say five tens, six wouldn't we if we were dual counting.

The place value chart shows the groups of 10 and the extra ones.

So I must write five in the tens on the place value chart because there are five groups of 10.

Five tens, six.

So well done if you noticed that.

Excellent work.

Okay, so the children have some dominoes and they arranged them like this.

Let's see if we can find some groups of 10 and extra ones to help us count them more efficiently.

So we can see there, I spotted that straight away, did you? Five, double five is 10.

So that was one group of 10.

Can we spot any more groups of 10 there? That's right, we know six and four sum to 10, don't they? They're a number pair to 10, so well done.

Hmm, what else can we see? Getting a bit more tricky here now.

Did you notice that one? So double four is eight and then we know eight and two more is equal to 10.

Oh, now let's have a look.

Can we see any others? That's right.

Oh, you may have noticed that there's a five and then there's a three and a two, which we know also is equal to five.

So we've got two fives there, which is equal to 10.

And then how many extra ones have we got there? That's right, we can see we've got double three, which is six, so there must be six extra ones.

So there are four tens and six ones.

So four tens and six ones is four tens, six, isn't it? And we can write that in the place value chart.

We know that four tens, six is the same as 46, so there are also 46 ones.

So well done if you noticed that.

The children are seeing how many times they can write their name in two minutes.

Each time Andeep writes his name, Laura makes a mark to represent it and there are the marks, look.

Let's see how many times he did it.

So how will we find out do you think? Any ideas about what we could do? That's right, we could put a circle, a ring round each group of 10, couldn't we? And that will help us count the tens.

So we can see he did one group of 10, two groups of 10, three groups of 10, four groups of 10.

Five groups of 10.

We have five groups of 10.

And then we can write that in the place value chart.

And then two more ones and there they are.

And then if we counted them all up in ones, how many would there be altogether? That's right, we know five tens are 50 and there's two more.

So that's 51, 52.

Well done if you noticed that.

Here's a task for the second part of our lesson then.

Work with a partner.

Pick an activity and ask your partner to make a mark for each time you complete it.

Then draw circles around the marks to complete the stem sentences and the place value chart.

Let's see how you got on with that then.

So Andeep's saying that, "My partner drew a mark for each time I kicked a ball into the goal." So that's what his activity was.

Okay, so let's see how many groups of 10 we've got.

So look, we've got one, two, three groups of 10.

And then we can see we have three in the place value chart to represent the three tens and then six more ones.

So then we write six in the place value chart in the ones column there to represent the six ones.

So if we counted them all together, how many would we have? That's right.

We know three tens are 30.

So we'd have 30, 31, 32, 33, 34, 35, 36 ones, wouldn't we? So well done if you did that.

So you've worked really hard today in today's lesson and hopefully you are feeling much more confident about counting larger groups of objects now.

So let's have a look at what we've learned in today's lesson then.

So we've found out that 10 ones are equivalent to one 10.

When counting larger groups, it is more efficient to group objects into tens, than count the tens and extra ones.

And we can work out how many there are in a group by counting in ones or by counting the groups of 10 and the extra ones.

So well done.

You've worked really hard and I've really enjoyed our lesson today.