Lesson video

Hello, my name's Mrs. Hopper and I'm really looking forward to working with you in this maths lesson.

So if you are ready to work hard, let's make a start and see what this learning is all about.

Welcome to this lesson on explaining the difference between consecutive even numbers.

And this comes from our unit on addition and subtraction facts within 10.

So by the end of this lesson, you should be able to explain the difference between consecutive even numbers and maybe use them to solve some problems. So let's have a look at what our lesson's all about today.

We've got some key words, they're words you might know already, but let's practise them together and then look out for them as we go through the lesson.

So I'll take my turn, then it'll be your turn.

So my turn, difference.

Your turn.

My turn, even.

Your turn.

My turn, consecutive.

Your turn.

Well done.

As I say, some of those you may well know already.

We're going to be thinking about consecutive but this time with even numbers.

So let's get into our lesson, see what we're learning about.

In the first part of our lesson, we're going to find the difference between consecutive even numbers.

And in the second part of our lesson, we're going to use that knowledge of consecutive even numbers and probably solve some problems. So let's get started.

And we've got Sam and Jacob helping us in our lesson today.

So, Sam and Jacob were watching birds in the garden.

Jacob tells a story about the birds.

First, there were six birds.

Then four birds flew away.

How many birds are left? So, Jacob knows that that means that we are starting with six, we're subtracting four and we don't how many we've got left at the moment.

Let's represent the problem as a bar model.

So, there were six birds and we've represented them as counters this time.

So there were six birds first, then four birds flew away and we've seen them fly down to become a part of our bar model.

So, how many birds were left? Four is two less than six, so there must be two birds left if you think about four and six on our number line.

And we can think if six is the whole and four is a part, the other part is two.

So we had two birds left.

Let's have a look at another problem.

There are eight children on the bus.

Six children get off the bus.

How many children are left on the bus? So we've got our children on the bus, but we've also got a bar model there to represent our problem.

So there were eight children on the bus.

Six children get off the bus.

How many children are left on the bus? We can see that there are two children left on the bus.

If eight is our whole and six is a part, the other part is two.

Jacob looks at the equations from both problems together.

So let's have a look.

So first of all, we had six birds in the garden and four flew away.

So there's our six, subtract four.

And then we had eight children on the bus and six got off the bus.

So we've got eight subtract six, and we can see our bar models there representing our problems. Jacob says the wholes and the known parts are all even numbers.

So we've got six as our whole and four as a part in our first bar model and eight as a whole and six is a part in our second bar model.

So yes, Jacob, well done.

You're right, they are all even numbers.

And then next to each other when we count in even numbers four, six, and eight, we can see that on the number line there.

Jacob says, "This means that both equations will have a difference of two," because the difference between two even numbers when we count is two.

So six takeaway four is equal to two and eight takeaway six is equal to two.

Let's count in even numbers and remind ourselves.

Are you ready? Count along the number line.

Let's start from two.

Are you ready? Two, four, six, eight, ten.

And we call those consecutive even numbers.

So two and four are consecutive.

Four and six, six and eight, eight and 10.

They're the even numbers that are next to each other when we count along in even numbers on the number line.

And we can say that consecutive even numbers have a difference of two.

We have to add on two more each time to get to the next even number or take away two each time to get back to the previous even number.

So four and six are consecutive even numbers.

They're even numbers that are next to each other on the number line.

Four and six have a difference of two.

We can say that six is two more than four and four is two less than six.

Time for you to check your understanding.

Can you use the number line to find more consecutive even numbers? And we've got some sentences there for you to fill in.

Hmm and hmm our consecutive even numbers.

Hmm is two less than hmm and hmm is two more than hmm.

So pause the video and have a go at seeing how many different ways you can complete those sentences with consecutive even numbers.

How did you get on? There were lots of different ones you could have chosen.

We've chosen two and four.

So we can say two and four are consecutive even numbers.

Can you see they're next to each other on the number line as even numbers? Two is two less than four and four is two more than two.

You could have had a few different pairs.

I wonder if you chose any of these.

You could have chosen four and six, six and eight or eight and 10.

I wonder which ones you chose to complete your sentences.

Maybe you found them all.

So using what you know, say which of these equations will have a difference of two? This is another time for you to check.

So, which of these equations will have a difference of two? Pause the video, have a think.

Think about the numbers on the number line.

Think about those consecutive even numbers.

Pause the video and then we'll talk about it together.

How did you get on? Which of them will have a difference of two? Which of them have consecutive even numbers as the minuend and the subtrahend, the whole and one of the parts? Let's have a look.

Eight subtract zero.

Eight subtract zero doesn't.

The eight and zero aren't next to each other on the number line.

They're not consecutive even numbers at all.

Eight and six though are consecutive even numbers.

If we think about counting in twos, two, four, six, eight.

We say them next to each other.

So they are consecutive even numbers and they have a difference of two.

Six and two.

Two, four, six.

No, they're not consecutive, are they? What about 10 and eight? Let's count backwards.

Ten, eight, six, four, two.

Yes, they are, aren't they? They will have a difference of two.

Three and two.

Three and two are consecutive numbers when we count in ones.

One, two, three.

So not consecutive even numbers.

Three is an odd number.

So no, that doesn't have a difference of two.

And what about four subtract two? Four and two, they are consecutive even numbers.

So they will have a difference of two.

Well done if you've got all those correct.

And Sam's reminding us consecutive even numbers have a difference of two.

She says, "I looked for the equations that had even numbers next to each other." Time for you to have some practise.

You're going to need some one to 10 cards and you're going to put them face down so you can't see the numbers.

Spread them out in front of you and then you're going to pick two cards and if they are a pair of consecutive even numbers, then you can leave them turned up.

If not, you can turn them back down and have another go.

And there's a stem sentence there to help you.

Hmm and hmm our consecutive even numbers to use when you find your pair.

And Sam says, "Mix the cards up when you've done it and play again.

Are there different pairs to find?" So pause the video, have a go at the game and then we'll have a talk about what we found out.

Did you have fun playing the game? So, Sam says, "You may have found lots of consecutive even numbers.

"First," she says, "I turned over four and six." Are four and six consecutive even numbers? Yep, four and six are consecutive even numbers.

Then she turned over two and eight.

Hmm.

"Two, four, six, eight," she says.

Two and eight are both even numbers but they're not consecutive.

But now she's got all those turned up.

We could say, well, two and four are consecutive even numbers, four and six are consecutive even numbers and six and eight are consecutive even numbers.

So she could have made different pairs from the ones that she turned up.

I hope you had fun playing that game.

Let's see what's in part two of our lesson.

So in the second part of our lesson, we're going to use our knowledge of consecutive numbers.

So, we've got Sam's cupcakes here.

Sam had six cupcakes, she gave four to her sister.

How many cupcakes did Sam have left? That was very kind of her to give some to her sister, wasn't it? So she had six cupcakes and she gave four to her sister.

Sam says, "We can represent this as a bar model.

Six is the whole and four is a part." So, six was all the cupcakes she had and four is the part that she gave to her sister.

Jacob says, "I will count back from six to find the difference of six subtract four." Sam says, "Wait, there's a quicker way.

Look at the whole and the known part." So our whole is six and our known part that Sam gave away is four.

Two, four, six.

"Oh," says Jacob, "They're consecutive even numbers." Four and six are consecutive even numbers.

Consecutive even numbers have a difference of two.

So that means the missing part is two.

Six takeaway four equals two.

Sam will have two cupcakes left.

So they use their knowledge of consecutive even numbers to help 'em solve the problem.

Let's solve another problem.

Jacob had six sweets.

He ate some after his dinner.

Now he has two left.

How many did he eat? Hmm, I wonder.

Jacob says, "I had six sweets at the start, so six is the whole.

I have two left, so two is a part." He's represented it with a part-part-whole model this time.

So six was his whole group of sweets.

He ate some, we dunno how many he ate, and he had two left.

So two was the part.

Sam says, "I know consecutive even numbers have a difference of two.

Does this help us?" Jacob said, "Yes, let's find the even number that comes before six." So there's six.

What's the even number that comes before six? It's four, isn't it? "I can see that four is the even number before.

This will be the missing part." Jacob says, "That means I ate four sweets." So he at four sweets and he had two left.

Because if six is a whole and two is a part, four is the other part.

Six and four are consecutive even numbers.

They have a difference of two.

Time to check your understanding with another problem.

Jacob has to read eight pages of his book.

He's read two pages so far.

How many pages does he have left to read? He's drawn us a part-part-whole model with the whole number of pages, eight, and the pages that he's read, two, filled in.

We've got to work out what the missing part is.

So pause the video, have a think about your consecutive even numbers and how that could help you to work out how many pages Jacob had to read.

How did you get on? So eight is the whole and two is the part we know he's read already, our known part.

We know that consecutive even numbers have a difference of two.

So we know that hmm plus two is equal to eight.

The even number before eight is six.

Eight takeaway two is equal to six.

So Jacob must have six pages left to read.

The difference between eight and six is two 'cause they are consecutive even numbers.

We knew the difference this time, so we knew that the number of pages he had to read was the even number before eight, which is six.

Now, Sam's hidden some numbers in some equations.

We know that in each equation there is a difference of two and we know something about the difference of two and consecutive even numbers, don't we? The whole number in each equation is an even number.

And so Jacob says, "The whole and the part must be consecutive even numbers." So he knows that there must be a difference of two.

So if we're taking a number away from eight and leaving two, we must be taking away a consecutive even number.

So let's have a look at that then.

In each equation, the hidden part must be two less than the whole.

So two less than eight is six.

So eight subtract six is equal to two.

Two less than six is four.

So six subtract four is equal to two, and two less than four is two.

So four subtract two must be equal to two.

Time for you to do some practise now.

You're going to use your knowledge of consecutive even numbers to find the missing numbers and complete the equations for these part-part-whole models.

And then you're going to find as many different ways to complete these part-part-whole models using consecutive even numbers and what you know about them.

You can see that there's a part of two for each of these.

So how could you fill in the hole in the other parts in different ways? Pause the video, have a go at your tasks and then we'll talk through them together.

How did you get on? Did you use your knowledge of consecutive even numbers to fill in the gaps in the part-part-whole models and equations? So in A, we knew that the whole was eight and one of the parts was six.

Eight and six are consecutive even numbers.

So the missing part must be two.

In B, six was the whole, and four was one of the parts.

Six and four are consecutive even numbers.

So the missing part must be two.

The difference is two.

So for C, we knew that 10 was the whole and two was a part.

So this time, we were looking for a consecutive even number to 10 so that we would have a difference of two.

And the consecutive even number that will do that is eight.

Eight and 10 are consecutive even numbers and they have a difference of two.

And for D, we knew that four was the whole and two is a part and we were looking for the other part.

Well, four and two are consecutive even numbers.

So the missing part must be two.

Four subtract two is equal to two.

And for the second part, we wanted you to use your knowledge of consecutive even numbers to fill in these part-part-whole models in lots of different ways.

So we've got a difference of two here all the time.

So we are looking for consecutive even numbers.

So we might have had four as the whole, two is a part and two is the other part.

Six and four as our whole and our other part consecutive even numbers.

So the other part, the difference must be two.

Eight and six are consecutive even numbers.

So the difference will be two.

And 10 and eight are consecutive even numbers.

So the difference, the other part, must be two.

I hope you had fun completing those tasks.

And we've come to the end of our lesson on explaining the difference between consecutive even numbers.

What have we learned? We've learned that consecutive even numbers have a difference of two.

And we can see that on the number line, the difference between two and four is two, between four and six is two, between six and eight is two and between eight and 10 is two.

And we can use this knowledge to solve missing number problems when two is a known part.

Thank you for your hard work and your thinking today.

I hope I get to work with you again soon.

Bye-bye.