Lesson video

Hello everyone, I'm Mrs. Crane and welcome to today's lesson.

In today's lesson, we're going to be exploring how we can use bar models to represent word problems. I'll explain all about that during the lesson today.

Don't worry about getting any equipment just yet, but what I would really like you to do for me please is try and turn off any notifications that you've got on your phone, tablet, or other device you're using to access today's lesson on.

And then, if you can, try and find somewhere nice and quiet in your home where you're not going to be disturbed today.

When you're ready, let's begin.

Okay, then, let's run through today's lesson agenda.

We're going to start off by looking at word problems as bar models, then for Let's Explore today, we're going to be looking at Your Turn.

Then we're going to be looking at division problems, and then it will be time for your Independent Task which will be completing bar models and solving equations.

And, we'll go through the answers together.

So, before we get started, please could you get yourselves a pencil, some paper, and some counters.

The counters could be multi link cubes, they could be raisins, they could be dried pasta, whatever you've got at home that you could use as a counter will be great.

Pause the video now to go and get those things if you haven't got them already.

Okay then, let's get started.

So, word problems. There are four bags of apples.

There are five apples in each bag.

How many apples are there altogether? So, do we know the value of each part? Well, I think we do.

We know that there are one, two, three, four bags of apples and in each bag, you can see them here, there are five apples.

The information we don't know is how many there are altogether, that whole part here.

So, let's think about how we can represent that just using the bar models.

So I've taken the apples off this bar model so I know that each of these represents five.

I've got it marked in here.

So I know that each of these bars, and there's one, two, three, four of them, is worth five.

So, I'm starting to think I'm going to mark them down like so.

So I've got five, ten, fifteen, twenty.

What did you notice that I did? Well, I counted up in my fives, four times.

So I'm going to write 5 x 4 = 20.

You can see them here, each of these counters is worth an apple.

Imagine that they're an apple.

So my question mark, I can now change it to tell me that there are now 20 apples altogether.

Next, then, a bag can hold five apples.

Mrs. Smith had 20 apples.

How many bags are needed for all of the apples? So, this time, Mrs. Smith had 20 apples.

The whole is 20.

One of those parts is worth 5.

We know that one of the bags, and here it is, can hold 5.

What do we not know? All right, wait a minute.

Well, we don't know how many bags she needs to put all of the apples in to be able to go, I'm assuming she wants to go and give them out.

So, we need to do something different this time.

We need to do 20 divided by five, because we know that each bag holds 5 apples, to find out how many bags Mrs. Smith needs.

How could we do that? How could we solve that? Well, I could put five in my head, 20 in my head, sorry, and roll my fives until I get to 20 because I know that that will give me my answer.

So, 20 in our heads, together with me, five, 10, 15, 20.

How many? Absolutely, my answer is four.

So my missing number, I know I need four bags to carry, oh, got carried away there, to carry all of the apples.

Your Talk Task today, it's your turn.

So, what I want you to do please, I'm just going to move myself so you can see the pause sign.

Is, I would like you to read this question and you're going to have a go at the Can You.

There were five cars driving to the airport.

Each car holds two people.

How many people were going to the airport? What I want you to do is think about, if you can, use counters to represent the parts or the whole.

And have a go at drawing the bar model.

So, please pause your video now to have a go at today's Talk Task.

Okay, welcome back, I'm just going to put you, put myself back so you can still see me.

So let's have a little bit of a discussion based on today's Talk Task.

So, five cars, each car holds two people.

We want to draw on, counters, use or draw counters sorry, to represent the parts of the whole, or the whole, and we want to draw a bar model.

So, here are my counters.

You can see there's two people in this car and there's one, two, three, four, five cars.

Now we're going to draw my bar model in.

Here you can see there's two people, and you can see it's marked on, and there are one, two, three, four, five cars.

Now, if you wanted to solve that equation, what would you need to do to solve it? Well, I would need to do five, times by two, is equal to 10.

You can see it represented here and you can see it represented here.

So my whole, my missing whole, is 10.

Right then, now what we're going to do is look at some slightly, I'm just going to move myself so you can see this part here, some slightly different word problems because these are division word problems. So, I have got 18 marbles, and I've shared them between three children.

Here they are, at the bottom here my three children that I've shared my marbles between.

How many marbles does each child get? So you can see here my whole is 18.

This time, I've split it into three, because there's three children I wanted to give the marbles to, and I've given each of them six.

What equation could we use to solve this? Well we could say 18 divided by three is equal to six.

This time, I have 18 marbles, and I've shared them between six children.

How many marbles do you think each child got? What equation do I need to use to solve this? So, I need to do 18 divided by six, and I need to find out what that missing number is to know how many marbles I gave to each child.

So, here's my whole, my 18, mark that on.

And now I'm splitting it into six.

Why did I split it into six? Well, each part here, is a child.

A child that I gave some marbles out to.

So, if I'm going to give them out, I'm going to give them a marble each.

Now, I don't actually have any marbles, I've got some counters I'm going to use just to represent those marbles.

So I've given them each one, and I've still got some remaining, because I've got one, two, three, four, five, six given out.

Let's give out another six.

Seven, eight, nine, 10, 11, 12.

13, 14, 15, 16, 17, 18.

Can I keep going? I can't, because I've given all of my marbles out.

How many marbles did each child get? Fantastic, each child got three marbles this time and there were six children.

So my answer is three.

Now, if you're feeling really confident, I'm just going to move myself again so I can see this bit of the question.

Then, once I've read the question, then you can have a go at drawing out the bar model and marking in the marbles.

So, this time, there are three children.

Each child has six marbles.

How many marbles are there altogether? So similar question, just a little bit different.

Pause the video now if you're feeling super confident to answer this question.

So, here you can imagine there's one, two, three children.

I know that each child has got six marbles but I don't know how many marbles I have actually got to give out.

So, this time, I'm going to put six, 12, 18.

So I know now that my whole is 18.

So I can put my answer here.

Oop, sorry, got carried away.

I can put my answer here because I know this whole here represents the 18 marbles that I gave out to three children.

Each child has six marbles.

I know these are counters but we can imagine they're marbles.

Right then, it is now time for your Independent Task today, which is using bar models to write equations.

Okay, for your Independent Task, what I would like you to do is complete the missing equations, bar models, and parts of the stories needed to solve the problem.

Don't forget you can use counters and drawings of the bar models to help you out.

This is question one, so you'll need to read through it and write in your equation.

Question two, again, different question, you'll need to read through that and mark in your equation, and question three, you'll need to read through the question, mark in your equation, and do anything else in the bar model or part of the story to help you.

Please pause your video now [Offscreen] to have a go at today's main independent task.

Don't forget to resume it once you're finished, so that we can go through the answers together.

Okay, welcome back.

Right then, question number one.

There are 24 children who sit at four tables.

Let's have a look at our bar model.

24, that's our whole, and one, two, three, four tables.

There are the same number of children at each table.

How many children sit at each table? Now, we've got it marked on here that there's six, that each part represents six, and we can see here that there are four of them so my equation is 6 x 4 = 24.

Question two, There are 24 children who sit at six tables.

There are the same number of children at each table.

How many children sit at each table? This time I've been given just my 24 here.

So I need to mark in, draw in, my six tables.

Let's check: One, two, three, four, five, six.

And now I'm goin to mark in my 24 children.

So here we've got one, two, three, four, five, six.

Seven, eight, nine, 10, 11, 12.

13, 14, 15, 16, 17, 18.

19, 20, 21, 22, 23, 24.

Oh, I have to stop there, I've given out all of my children to a table.

Now, how many children sit at each table? So how many does each part represent? You see it here, it's four.

So I can write 26, 26? Isn't it 26? 24, divided by the six, because there's six tables, gives me four.

And question number three.

There are four children at each table.

There are [Silent] Tables, how many children are there altogether? So I've written in my equation, 4 x 6 = something.

I knew there was six because I could see it was marked off, one, two, three, four, five, six.

So I can mark that into my question here.

There are six tables.

Now, I want to know how many children there are altogether.

Now I know that four times by six, is equal to 24.

I actually used 2 x 3 to give me, no not 2 x 3 sorry, 2 x 6 to give me 12 then doubled the answer to give me 24.

If you'd like to, please ask your parent or carer to share your work from today on Twitter by tagging @OakNational and using the hashtag LearnWithOak.

Fantastic work today, don't forget to go and complete your quiz to show off all of your fantastic word problem and bar model knowledge.

Hopefully I'll see you again soon for some maths.

Thank you and goodbye.