Lesson video

Hello.

I'm Mrs. Cayley and I'm going to help you with your learning today.

So in today's lesson we will be finding one more and one less than a number using representations, and we'll describe this accurately.

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

Here's the outcome of today's lesson.

I can recognise that the number before a given number is one less, and the number after a given number is one more.

Here are keywords for today's lesson.

Can you repeat them after me? My turn.

One more.

Your turn.

My turn.

One less.

Your turn.

My turn.

Before.

Your turn.

My turn.

After.

Your turn.

My turn.

Number line.

Your turn.

Well done.

So one more means the number after a given number when we are counting, it's a greater amount, a bigger amount by one.

One less means the number that comes before a number when we count.

So it's a smaller value.

It's one fewer.

A number that is before another number comes earlier when you count, and a number that is after comes later when you count.

A number line is a line with numbers written on in the correct position, in the correct order.

Let's have a look at today's lesson outline.

So today's lesson we will show one more and one less than a number using representations and describe this accurately.

First of all, we will look at one more and one less, and then we'll solve problems using one more and one less.

So let's start with the first part of the learning.

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

We've got Izzy and Jacob.

Let's say the number words in order.

Can you say them with me? One, two, three, four, five, six, seven, eight, nine, 10.

Should we try them again on our fingers? Let's see if you can do it with me.

One, two, three, four, five, six, seven, eight, nine, 10 Let's say the number words in order again.

This time there'll be some cubes to represent each number.

Zero, one cube, two cubes, three cubes, four cubes, five cubes, six cubes, seven cubes, eight cubes, nine cubes, 10 cubes.

Let's do it again with our fingers.

You ready? Zero, one, two, three, four, five, six, seven, eight, nine, 10.

What do you notice here? Have a look at the towers of cubes.

Think about what you notice.

It looks a bit like a staircase, doesn't it? Each time the towers of cubes are getting bigger and bigger, one more each time.

So we are starting with zero cubes, and we've got one cube, two cubes, three cubes, four cubes, five cubes, six cubes, seven cubes, eight cubes, nine cubes, and 10 cubes.

Izzy said each number is one more than the one before and I can see that one extra cube is being added.

That's the red cubes.

So one is one more than zero.

Two is one more than one.

Three is one more than two.

Four is one more than three.

Five is one more than four.

Six is one more than five.

Seven is one more than six.

Eight is one more than seven.

Nine is one more than eight, and 10 is one more than nine.

So we can go all the way up the staircase by adding one more each time.

Let's try going backwards.

So nine is one less than 10.

Eight is one less than nine.

Each number is one less than the one after.

So we can come down the staircase and work out one less than each number.

Seven is one less than eight.

Six is one less than seven.

Five is one less than six.

Four is one less than five.

Three is one less than four.

Two is one less than three.

One is one less than two, and zero is one less than one.

Did you see how he came down the staircase to work out one less? Each number is one more than the one before.

Can you see the cubes this time? One and one more makes two.

Two and one more makes three.

Three and one more makes four.

Four and one more makes five.

One more than one is two.

One more than two is three.

One more than three is four.

One more than four is five.

Let's try going the other way.

Each number is one less than the one after.

So let's start with five cubes.

One less than five is four.

One less than four is three.

One less than three is two.

One less than two is one, and one less than one is zero.

Each number is one less than the one after.

One less than five is four.

One less than four is three.

One less than three is two, and one less than two is one.

And we can keep going.

One less than one is zero.

You could try making towers of cubes like this to check.

We can show one more and one less on a number line.

Here's a number line.

You can see all the numbers from one to 10 have been put on the number line in the correct order.

The number after a given number is one more.

So if we start at zero and we try to find one more, we do one jump on the number line and we end up at one.

So one is one more than zero.

One more than one is two.

Again, we can jump on the number line, one jump.

One more than two is three.

One more than three is four.

One more than four is five.

One more than five is six.

One more than six is seven.

One more than seven is eight.

One more than eight is nine, and one more than nine is 10.

Can you see how we've hopped along the number line, adding one more each time? We can show one more and one less on a number line so we can try hopping backwards on the number line to find one less.

The number before a given number is one less.

So if we start at 10 and we hop backwards, one less than 10 is nine.

One less than nine is eight.

One less than eight is seven.

One less than seven is six.

One less than six is five.

One less than five is four.

One less than four is three.

One less than three is two.

One less than two is one, and one less than one is zero.

If you've got a number line or a ruler, you could try this yourself.

Remember to hop forwards to find one more and backwards To find one less.

We can use the number line to work out one more and one less.

Can you see the number line there? And you can see the hops showing us which way to go, one more or one less.

So we go forwards for one more and backwards for one less.

So one more than three.

Here's the number three.

One more than three is four.

So we need to hop one more on to get to four.

One less than three is.

So which way are we going to hop? We're going to hop backwards.

One less than three is two.

One more than two is.

So which way are we going to hop forwards or backwards? We're going to hop forwards on the number line.

So one more than two is three.

And one less than two is.

So find two on the number line.

One less than two is.

It's one.

Each number is one more than the one before and each number is one less than the one after.

Let's use the number line to work out these ones.

Mm is one more than three.

So there's three.

Something is one more than three.

Which way are we going to hop on the number line? We're going to hop forwards or backwards.

That's right, we're going to hop forwards.

Something is one more than three.

It's four.

Four is one more than three.

Mm is one less than three? So there's three.

Which way are we going to hop on the number line? Yes, we're going to hop backwards on the number line.

So two is one less than three.

Mm is one more than four.

So which way are we going to hop on the number line? We're going to hop forwards on the number line.

Five is one more than four, and something is one less than four.

So we are going to hop backwards on the number line.

Three is one less than four.

Each number is one more than the one before and each number is one less than the one after.

Let's use the number line to help us work these ones out.

One more than mm is one.

One more than something is one? Yes, it's zero.

One more than zero is one.

One less than something is one? Yes, one less than two is one.

One more than something is two? Yes, one more than one is two.

And one less than something is two.

Yes, one less than three is two.

Each number is one more than the one before.

Each number is one less than the one after.

Let's check your understanding.

who is correct? Izzy said four is one more than five.

Jacob said five is one more than four.

Pause the video and think about who's correct.

It's Jacob.

Five is one more than four.

I can see on the number line that five is one more than four.

Let's check your understanding again.

Who is correct? Izzy said three is one less than two.

Jacob said two is one less than three.

Pause the video and think about who you agree with.

Yes, it was Jacob.

Two is one less than three.

Let's check on the number line.

Two is one less than three.

Let's check your understanding again.

Who is correct? Izzy said three is one more than two.

Jacob said three is one less than two.

Pause the video and think about who is correct.

That's right, Izzy was correct.

Three is one more than two.

You can see on the number line that three is one more than two.

Who is correct this time? Izzy said four is one more than three.

Jacob said four is one less than five.

Pause the video and think about who is correct.

So this time Izzy and Jacob were both correct.

Four is one more than three.

You can see that on the number line.

And four is one less than five.

You can see that on the number line too.

So they were both right this time.

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

Can you use the number line to complete the table? So one is one more than something.

Two is one more than something.

Three is one more than something.

Four is one more than something, and five is one more than something.

You can use the number line to help you or you could get cubes out.

This is the second part of your task.

This time we're working out one less.

So see if you can use the number line or cubes to help complete the table this time.

Zero is one less than something.

One is one less than something.

Two is one less than something.

Three is one less than something, and four is one less than something.

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

How did you get on with your task? Did you use the number line to complete the table? So I filled in the answers here for you.

One is one more than zero.

Two is one more than one.

Three is one more than two.

Four is one more than three, and five is one more than four.

Can you see a nice pattern in the answers there? They're going up by one each time.

How did you get on the second part of the task? Did you use the number line to complete the table here? So we had zero is one less than one.

One is one less than two.

Two is one less than three.

Three is one less than four, and four is one less than five.

Can you see the pattern in the answers there? They're going up by one each time.

Let's move on to the second part of the lesson.

We will be solving problems using one more and one less.

Here's a problem for us to think about.

Izzy is walking to school.

It takes four minutes to get to the park.

It takes one more minute to get to school.

How many minutes does it take to get to school in total? So it takes Izzy four minutes to get to the park and then one minute to get to school.

What's the total amount of time it's taken her? It took five minutes because five is one more than four.

Do you agree? Here's another problem for us to look at.

Jacob is catching a bus to go home.

It takes two hours to get to the first stop.

It takes one more hour to get to his stop.

How many hours does it take in total? So it takes him two hours to get to the first bus stop and then one more hour to get home.

How many hours is that altogether? It took three hours altogether.

Three is one more than two.

So three hours is one more hour than two hours.

Here's another problem for us to think about.

Izzy has four pounds in her piggy bank.

She takes one pound out to spend.

How much does she have left? There we go, she's taken one pound out, and she said, "I have three pounds left." Three is one less than four.

Let's check your understanding.

Jacob has five conkers in his pocket.

He gives one to Izzy.

How many conkers does he have left in his pocket? Pause the video and think about the answer to this one.

And you could use cubes to check.

So he's giving one conkers to Izzy and he said, "I have four conkers left." Four is one less than five.

Let's look at this one together.

What do you notice here? Three is one less than four and four is one more than three.

What do you notice about those numbers? So here are the towers of cubes, three cubes and four cubes.

Izzy said each number is one more than the one before.

So we can always add one more onto a number to find the next number.

And Jacob said each number is one less than the one after.

So we can take one cube off to find the number that is one less.

Did you notice how the numbers swap round? So three is one less than four and four is one more than three.

What do you notice here? Four is one less than five and five is one more than four.

Again, the numbers have swapped round, haven't they? So Izzy said each number is one more than the one before, and Jacob said each number is one less than the one after.

Let's check your understanding.

Is this true or false? So is it right or is it wrong? One more than three is the same as one less than five.

You could use the picture to help you.

Is one more than three the same as one less than five? Pause the video and think about this one.

This one is true.

I can see that one more than three is four and one less than five is four.

So the answer to both of these is four.

Is this one true or false? One more than two is the same as one less than four.

You could use the picture to help you.

Pause the video and think about this one.

Yes, this one's true as well.

One more than two is three and one less than four is three as well.

So three is the answer to both of these.

Let's check your understanding, which numbers could fill the gaps? One more than mm is the same as one less than mm.

What numbers could go on the gaps? Have a look at the pictures to help you.

So we could say one more than one is the same as one less than three.

That's from the first picture, isn't it? Both of those answers are two.

Or we could say one more than two is the same as one less than four.

That's the middle picture.

Both of those answers are three.

Or we could say one more than three is the same as one less than five.

We can see that in the last picture.

Both of those answers are four.

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

Can you write a story to go with these sentences? So we've got four is one more than three and three is one less than four.

And you can see from the towers of cubes that four is one more than three and three is one less than four.

Then we've got five is one more than four and four is one less than five, and you can see from the picture that five is one more than four and four is one less than five.

So can you think of some stories a bit like Jacob and Izzy's stories about conkers, or pound coins, or pennies where they're finding one more and one less than these numbers, and you could write or draw your stories or you could try them out with a friend.

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

How did you get on with the task? Did you write a story to go with the sentences? So four is one more than three.

So Izzy said, "I had three conkers and I got one more." And you can see on the number line that four is one more than three.

What about three is one less than four? Jacob said, "I had four conkers and I gave one away." And we can see on the number line that three is one less than four.

What about five is one more than four? Izzy said I had four coins and I got one more.

So I can see that five is one more than four, and four is one less than five.

I can see Jacob said, "I had five coins and I gave one away." Four is one less than five.

What stories did you come up with? Can you tell them to a friend? We've got to the end of our lesson.

Today we were showing one more and one less than a number using representations and describe this accurately.

This is what we've learned.

The number before a given number is one less.

The number after a given number is one more.

We can use a number line to help find one more and one less.

A variety of representations, including a staircase of blocks can be used to show one more and one less.

So you can always use a number line or cubes or counters to help you find one more and one less.

Well done, everyone.

See you next time.