﻿Hello, and welcome to lesson 10 for Lower Key Stage 2, all on fractions. My name is Mr Bee and I'm going to be your teacher today. Do you remember when Mrs. Barga asked you to make as many shapes as you could using unequal parts? I'm sure she said it was a triangle that you had to use. We know you will have had lots of fun constructing whole shapes when we gave you the part. And we said that this time the parts were unequal. I wonder if any of your shapes look like these? Did you remember to say the sentence for each one that you made, check the bottom of the screen right now. The whole is made out of, unequal parts. So now you've learned that wholes can be made of equal and unequal parts. For today's lesson though, we are just going to be focusing on equal parts. All right, let's get started. On this screen you can see one, a five equal parts of a shape. I wonder if you can make a length to show me what the whole could look like. I have got two different versions here. I wonder if you might be able to help me spot a mistake that I could have made. So in my first model, you can see I've got one, two, three, four, five. Oh. But it looks like I've got one more. So how many parts will I have in the whole? Yes, you're right. That would be six. So that model must be incorrect because there are five more parts. In the next model you can see I've got, one two, three, four, five equal parts. So this one must be correct because my whole had five equal parts altogether. All right. Now it's your turn. How many different wholes can you draw? Think really carefully about what else it could look like, If we know that one square is one of five equal parts. It doesn't have to go in a row like my last models. I want you to try and be really creative and use your imagination. I wonder how many you can find. Remember to draw five equal parts and not five more, because that was the mistake that we have just seen together. I put together some examples that I came up with, and I wonder if you had any similar. All of my shapes here, have got by equal parts. We've got one part, two equal parts three equal parts, four equal parts and five equal parts. Here we've got one equal part, two equal parts, three equal parts four equal parts and five equal parts. Let's try a different colour now. Here we've got one equal part, two equal parts, three equal parts, four equal parts and five equal parts. They all look different, but they all have five equal parts. Wow! You're getting really good at this. So we're going to look at this in different ways. I have cut a ribbon into five equal parts. Here's one part of my ribbon. How long was my ribbon to start with? You might want to pause the video and have a go at drawing what it might look like. All right. Let's have a look together. If one, a five equal parts are in the whole, then the whole must have five parts. How did you get on? Here is one part of a piece of ribbon which has four equal parts. Which ribbon below do you think it would match to? Now would be a good time to pause the video and to think about which one it could match to. Remember there are four equal parts to the ribbon. All right, let's have a look at the ribbons below. So in the first example, we have got one, two, three, four equal parts. So it could be that one. And the second example we have one, two, three, four equal parts. And the third example, we have one, two, three, four equal parts. And in the final example we have one, two, three, four, five equal parts. Now we said that the whole ribbon have to have four equal parts. So if can't be the fourth example. It looks to me that my part of ribbon at the top is much too big to be the third example. And just much too big to be the second example. Did you think that it matched the first example? If you did, you were right. And you're getting really good at spotting equal parts of a whole. Wow! You're getting so good at this now. We can start and look at this a little bit differently. Here is one team of four equal teams in a whole class. I wonder how many children that will be in the whole class and how we can work this out. If we know one of the equal parts, can we work out what the size of the whole class could be? You're right. We can. We've learned that already. Okay. Let's think carefully about this. So, if one equal part is five children, let's draw the other equal parts. Now let's remember not to draw four more equal parts. Look, full parts all together. So now, we have a whole class of four. And I know that four groups of five children of four times five must be 20. I could also have skip counted in fours or in fives. Let's try that. We could have five, 10, 15, 20 children in the whole class. Now let's really think carefully about that. In one equal part, there are five children. In two equal parts, there are, did you say 10 children? There are all 10 children. In three equal parts, there are 15 children. And in four equal parts, there are 20 children. So, there are 20 children in the whole class. This example changes slightly. And I wonder if you could work out, work it out by yourself. This time, have you noticed that there are four children in each team? It says, it is one of four equal teams in the whole class. Can you work out how many children would be in the whole class? Have a go. Okay, let's see how you did. If I know that one group has four children in, then, two groups is going to have eight children in, three groups of four is going to have 12 children in and four groups of four is going to have 16 children. So the whole class would have 16 children. Wow! You're getting so good at this. In this lesson we've been able to construct the whole, when we know what an equal part is and how many equal parts there are. Now I know you will be ready for a challenge right now. Have a look at the table on the screen. I'm going to show you a part of a whole. I'm going to tell you how many equal parts they're and your task is going to be to draw what the whole could look like. Let's have a look at the first one. One triangle is apart. There are three equal parts. What could the hole look like? Now would be a good point to pause the video and to draw what the whole could look like. How did you get on? Here's one that I came up with. One part, two equal parts, three equal parts. Now yours might look different but as long as all of the parts are equal and there are three equal parts, you could still be correct. All right, let's try the next one. One rectangle is apart, there are five equal parts. Pause the video and see if you can draw what the whole parts look like. Did you remember that it needed five equal parts? Here's what mine looks like. One part, two equal parts, three equal parts, four equal parts and five equal parts. Now remember we have got half exactly five equal parts and not five more equal parts. Cause that would be six equal parts. Let's have a look at the last one. This time I've got one group of four children. They're all four equal parts. I wonder if you can draw what the whole could look like. Now remember to use your imagination and to be creative when you draw this. How did you get on? Here's what mine looks like. Now yours might look very different because if you've still got 16 as the whole, then when you're in the dinner hall 16 children might look very different to 16 children in the classroom or 16 children lining up to go to assembly or 16 children playing outside on the yard. So as long as you have got 16 is your whole, then you are correct. You have done so well today looking at equal parts in a whole. I'm going to leave you with this practise activity for you to have a go at home. It's very similar to the last activity that we've just done and it will really help you practise the skill of looking at equal parts. So, I know that I've got one circle, but there are two equal parts. I wonder if you can pause the video now and try and draw what the whole could look like. It was my example. One part, two equal parts. Now remember yours might look a little different because you might have drawn the circles in a different way. They could be on top of each other. They could be diagonal, but as long as there are two equal parts, you will have got it correct. But we must remember that we're not adding two extra parts because that would be three equal parts all together. All right. Let's have a look at the next one. This time, I've got two shoes. And there are three equal parts. Pause the video and can you draw how many shoes there would be all together. Let's see how you did. One group of two shoes is two shoes. Two groups of two shoes is four shoes. Three groups of two shoes is six shoes. So my whole was six shoes. This time I've got one part of a ribbon. There are four equal parts. What could the hole look like? Pause the video now and see if you can have a go a drawing what it could look like. Let's have a look together. One equal part two equal parts three equal parts and four equal parts. Now remember, yours might be different. It might look different. Yours could be vertical, it could be diagonal. As long as there are four equal parts, you would have got it correct. The next one is a bit of a challenge. This time, I'm going to show you the whole. This whole is made up of five equal parts. I would like you to try and draw what one of those parts could look like. If you have colours, you could colour to show what it would look like. If not, you could just label the yellow box Y and the red box R. So, this time we need to split our box into five equal parts. So let's try that together, one equal part, two equal parts, three equal parts and four equal parts. So, one of the parts should look like so. And finally, for your final challenge today. If I have got three dogs in one group, and this is what my whole looks like, how many equal parts do I have? I bet you've been working really hard. We've got one equal part, two equal part, three equal parts, four equal parts, five equal parts and six equal Parts.

In this lesson, we will investigate the ways we can build a whole once we know the size of one equally divided part..

In this lesson, we will investigate the ways we can build a whole once we know the size of one equally divided part.. Resources provided by NCETM (CC BY-NC-SA: https://creativecommons.org/licenses/by-nc-sa/4.0)

Maths

Y3 Maths

Key Stage 2

Year 3

Explore different contexts for building a whole when a part is known

Fractions: parts and wholes

UNIT

Explore the whole and part relationship in familiar contexts, using area, linear and quality models

Explore the whole and part relationship and generalise that a part is always smaller than the whole

Explore the Concept of 'Equal' and 'Unequal' Parts

Embed the concept of equal parts and unequal parts

Develop understanding that equal sized parts do not have to look the same

Compare the size of parts when the whole is defined using familiar contexts

Explore that size of part is relative to the size of the whole using familiar contexts

Consider part whole relationships within the context of quantity models

Build a whole when a part is known

Lesson overview:Explore different contexts for building a whole when a part is known

Core Content

Fractions: parts and wholes: