Lesson video

Hello mathematicians.

It's Miss.

Charlton here and I have got Hedwig but she's a little bit nervous to say hello today because one of my pupils gave her a new scarf to wear and she's wearing it and I think she looks great but she's a little bit anxious to see you.

So we'll need to persuade her to come out.

Are you ready? Say "Please come out Hedwig come out, come on." Can you hear them Hedwig? Come out! Come out! there she is.

Doesn't she look fantastic in her new scarf.

Really good at keeping her warm.

Well done for being brave and coming and showing us Hedwig.

You can go and relax there now while we start our maths lesson.

Let's find out what we're going to do today.

We are going to use the Make 10 strategy to subtract a 1-digit from a teen number.

So, this is part two we're going to carry on practising if you missed part one.

That's absolutely fine you're going to enjoy this lesson anyway.

We're just going to recap it.

So, you'll be fine.

So we're going to recap the 'Make 10' strategy and then we're going to practise using that 'Make 10' strategy to solve subtraction equations then you'll do your independent task and your end of lesson quiz.

Today you're going to need a pencil and some paper and it might be helpful to have some objects to help you count.

If you want to use the objects to help you.

So, you could use something like raisins.

You could use nuts.

You could even use tea bags.

If you've got any paper clips or even some counter if you got those at home.

But if you don't have anything to help you.

That's fine you can use the pictures that I'll provide.

Let's start off with our star words.

Get those hands ready.

Hands up star words.

Make 10, partition, subtraction.

Let's see when those pop up in today's lesson.

Let's start ourselves off exploring with the equation 12 subtract seven.

Now we could do that on a number line.

We could try and do it on our fingers but it will be a bit tricky.

So, what we're using is the Make 10 strategy to be able to make our counting really efficient, really quick, and really accurate.

So, let's have a look and see how we would do that.

The first thing we need to do is? What is it? Make 10! Well done, let's make 10.

I don't know if you can see my 10 on the screen.

There you go that's 10.

We need to make 10.

So, the first thing we're going to do for this equation is to make 10.

I know that 12 subtract two is equal to 10 because 12 has got two ones and two has go two ones.

So, I just need to take those away and I am left with a 10.

So, 12 subtract two is equal to 10.

So, I've made 10 but how do I get that two where do I get it from.

I get it from the number seven which I can partition.

So, I'll take my seven, I'll put it in a bond.

And I know that I need to make one of those a two and the other one must be a five because two and five is equal to seven.

Seven subtract two and then the other part is a five.

So, to make 10 we do 12 subtract two is equal to 10.

Then, I take that 10 and I subtract the remaining part which is five.

10 take away five is equal to five.

So, 12 subtract seven is equal to five.

I made 10 and then I took away the remaining part.

Can you see how I have crossed them off on the cubes? So, you can double check it anyway.

There are 12 cubes, a group of 10 and two more.

And I've crossed off seven.

One, two, three, four, five, six, seven and I'm left with five.

So, I know that I counted accurately there because I checked it with my cubes.

Let's try another one together.

This time I'm going to show you it.

I'm going to show you how to do it using some objects.

Watch carefully.

So, we've got the equation as we just did 12 subtract seven.

So, I'm going to show you.

The first thing we have to do is to Make 10.

How do I make 10.

I know that 12 subtract two is equal to 10 because they both have the same number of ones.

There's one, two ones there and two ones there.

So, if I take those away, I'm left with a 10.

So I'm going to use that seven to help me partition.

I'm using pecans nuts here.

Be careful not to eat any of them.

One, two, three, four, five, six, seven.

So, I've got seven and I'm going to break that down, partition it.

I know that one of my parts has to be a two because I need the two to make 10.

So, two go in there, and then what's left.

That goes in the remaining part.

One, two, three, four, five.

So the remaining part to subtract is five.

I made 10 by subtracting the two.

So, then I used that 10 to subtract the remaining five which is equal to five.

So, 12 subtract seven is equal to five.

Right, now let's try again with another number with number 14.

This time we're going to do 14 subtract seven.

So, I've got my cubes there.

Can you see I've got 14 cubes, in a group of 10, and four more.

And I've crossed them off so we can check the at the end.

But the first thing that we need to do is make 10! How do we make 10? Well I know that 14 take away four is equal to 10 because they put the same number of ones.

Four ones and four ones so I'm going to use the number seven to partition it to get to the four.

So, I'll partition the number seven into four.

And then what else makes seven? Four, five, six, seven so the parts are four and three.

So, then I can take that remaining three away from the 10.

10 take away three is equal to seven.

So 14, oops, silly me.

14 take away seven is equal to seven.

Let's double check with the cubes shall we.

We had 14 cubes 10, 11, 12, 13,14, let's subtract seven.

One, two, three, four, five, six, seven and what's left? One, two, three, four, five, six, seven, 14 subtract seven is equal to seven.

Let's try another together.

This time we've got 15 subtract eight.

The first thing that I need to do is Make 10.

Well done! So, I've got my 15 cubes and I need to subtract eight.

What do I need to take away from 15 to make 10? well I can see it's got five ones so it must be 15 take away five to equal 10.

Where do I get the five from? I partition the eight.

There's my eight.

I know that one of the parts has to be a five.

So, that I can make 10.

So, the remaining part must be three because five plus three is equal to eight.

10 subtract three is equal to seven so 15 subtract eight is equal to seven.

Now it's your turn to do your independent task.

You're going to do exactly the same as what we've just done but don't worry we'll go through one together first.

In this example, it's 15 subtract seven.

The first thing we have to do is to make 10.

15 subtract five is equal to 10.

We're using the same example to try and make sure that you can get it really solidly in your head.

Then, the number two so first I make 10.

Second, I partition which number do I partition? The seven because I'm subtracting seven so there's my bond.

Seven must be partitioned into five because I need to make that one to 10 and the remaining part is two.

10 subtract two is equal to eight.

So, 15 subtract seven is equal to eight.

Now it's your turn to have a go at those examples there.

You've got two lots of it.

Independent task one and independent task two and then when you've had a go at those.

Come on back and we will check the answers together.

They get a little bit tricky at each time because I've missed off different parts of the marks each time.

So, you have to have to fill in more boxes.

If you get stuck don't worry have a go and see how you get on.

How did everybody do? Let's see we'll go through 16 subtract seven.

16 subtract six is equal to 10 because I know I had to make 10.

So, I partitioned the number seven into a six to help me make the 10 and one remaining because six plus one is equal to seven.

Then, I subtracted that one remaining amount 10 subtract one is equal to nine.

So, 16 take away seven is equal to nine.

12 subtract seven.

I needed to make 10.

I know that 12 subtract two is equal to 10 because they've got the same number of ones.

Then, I needed to partition the number seven.

I partitioned it into two to help me with my make 10 bond, my make 10 strategy and the remaining part was five because two plus five is equal to seven.

Then, I can use that 10 to subtract the remaining five.

10 take way five is five.

12 take away seven is five, and the last one 12 take away eight.

I need to make 10, 12 take way two is equal to 10.

Let's partition to give me the two.

Eight can be partitioned into two and six.

I use that 10 to subtract the remaining part which is a six.

10 take away six is equal to four.

So, 12 take away eight is equal to four.

You all did a fantastic job today! I'm so proud of you, that was such a tricky lesson and you really did well with it.

Shall we have.

Let's think, shall we have a roller coaster.

Shall we have a hulk clap.

Shall we have Let's have two claps and a whoa.

Are you ready? Whoa! Can you do that? Brilliant shall we wake up Hedwig and tell her what we did? Wakey wakey Hedwig! Look at you and your smart scarf.

Now today Hedwig we had a great time exploring partitioning.

We needed to use the make 10 strategy to help subtract numbers from a one digit number from a teens number.

We used the make 10 strategy because we know that it will help us do it really really quickly, efficiently, and accurately.

So, the first thing we had to do was make 10.

To make 10 we needed to partition the ones to steal them to put them over into the tens.

Then, we subtracted those and we were able to subtract the remaining amount which meant that we did some really accurate subtraction equations.

Do you understand Hedwig? I think she enjoyed that and she is nice and warm in her scarf.

Well done today everybody you can now head over and do your quiz and I will see you again very soon.

Bye bye.