Lesson video

Hi everyone, I hope your all okay.

Today we're going to be Creating and Labelling Bar Models, so I hope you're ready to do some maths.

If you can try and find some quiet space for to work.

In today's lesson, we'll be solving addition word problems, solving subtraction word problems, then I'd like to have a go at the worksheet and then a quiz.

For today's lesson you will need a pencil, a ruler, and some paper.

Pause this video now to get this, if you have not got it already.

Here's a word problem.

There are five apples and four oranges.

How many pieces of fruit are there all together? How can I represent the maths in this word problem, using a bar module? What is known and what is unknown? The value of one part is five, and the other part is four, and the whole is the unknown.

To find out the whole, I need to add my parts together.

The equation is five plus four is equal to the unknown.

Now let's have a go at creating this bar model.

First I draw the first part which is five, because there are five apples.

So I draw one, two, three, four, five squares.

I now need to label it five.

The other part is four, as there are four oranges.

So I will draw one, two, three, four squares.

I now need to label this part four.

Now the whole is unknown, because the question is asking us how many are there altogether? So I need to label that the whole is unknown.

After drawing and labelling my bar model, this will help me to see what equation I need to do.

This will be five plus four is equal to the unknown.

I can now solve my equation.

Five plus four is equal to nine.

Let's try one together.

The fruit seller has six apples in a bowl.

He adds three more.

How many apples are in the bowl now? How can I represent the maths in this word problem using a bar model? What is the value of my parts? What is unknown? Pause the video and have a go.

Now let's have a go at creating this bar model.

First, I draw the first part which is six, because there are six apples in the bowl.

So I will draw one, two, three, four, five, six squares.

I now need to label it six.

The other part is three as he adds three more.

So I will draw one, two, three squares.

I now need to label this part three.

Now the whole is unknown because the question is asking us how many there are now.

So I need to label that the whole is unknown.

After drawing and labelling my bar model, I can see what operation I need to use.

To work out our whole, I need to add two parts together.

So my equation will be six plus three is equal to the unknown.

Then I can solve my equation, six plus three is equal to nine.

Here's a new one.

There are 12 apples and four oranges.

How many pieces of fruit are there altogether? Have a go at this one by yourself.

Represent the word problem as a bar model and write the equation.

Pause the video now and a have ago.

And here's the answer.

First I draw the first part, which is 12, because there are 12 apples.

I now need to label it 12.

The other part is four, as he has four oranges.

I now need to label this part four.

Now the whole is unknown, because the question is asking us how many there are altogether.

So I need to label that the whole is unknown.

After drawing and labelling my bar model, I can write my equation.

12 plus four is equal to the unknown.

Finally, I can solve my equation.

12 plus four is equal to 16.

Now this question is different to the first three, because we are starting with the whole.

When we start with the whole, what operation are we using? That's right, subtraction.

There are nine bananas, four yellow and the rest are green.

How many bananas are green? What is nine to us? My whole is nine, so I will draw my blocks with a ruler.

I need to label that the whole is nine, because there are nine bananas.

I then need to label that one part is four, because four of these nine bananas are yellow.

You may also want to shade in with your pencil.

I can now see on my bar model that this part here is unknown, so I can label this too.

Looking at my bar model, I can see what calculation I need to do.

Because I need work out a part, my equation is nine take away four is equal to the unknown.

Now I know my calculation, I can solve it.

Nine take away four is equal to five.

Let's try one together.

The fruit seller has nine carrots.

He sells five of them.

How many does he have left? What information do I know? Pause the video and have a go at representing this in a bar model.

I know he's starting with nine and he sells five, which means my number will get smaller.

If my number is getting smaller, I know I am subtracting.

My whole is nine, so I will draw my blocks with my ruler.

I need to label that the whole is nine because the fruit seller has nine carrots.

I then need to label that one part is five.

Again, you might also want to shade it with your pencil.

I can see on my bar model that this part here is unknown.

Now, by looking at my bar model, I can see that nine take away five is equal to the unknown.

Finally, I can solve this equation.

Nine take away five is equal to four.

Here's one more.

There are 16 bananas.

Four of the bananas are yellow and the rest are green.

How many are green? Have a go at this one by yourself.

Represent the word problem as a bar model and write the equation.

Pause the video and have a go.

So this is how it should look as it's been drawn.

Firstly, I know the whole is 16.

Because there are 16 bananas, so I'll draw 16 blocks.

Don't forget to label it.

Four are yellow, so that means one part is four.

Label it four, and then you may want to colour in four blocks to help you.

This means that the other part is the unknown.

Also remember to label this.

What is my equation? 16 take away four is equal to the unknown.

And then we know 16 take away four is equal to 12.

Amazing, well done.

Have a go answering these word problems. First you need to read the questions and work out what operation to use, whether it's addition or subtraction.

I like to underline any key words or numbers in the question too.

Then draw your bar models and work out the answer.

Pause the video now, and then press play when you're ready for the answers.

And here are the answers for question A and B.

And here are the answers for questions C and D.

If you'd like to share your work with Oak National, please ask your parent or carer to share your work on Twitter, tagging @OakNational and #LearnwithOak.

Well done for today, you've tried really hard.

I want to see what you can remember, so please make sure when the video has finished, you go onto the next slide and you complete the quiz.

Great job.