﻿Hi, it's Mrs. Barker again. In this lesson we're going to be using the language part, whole, equal and unequal. And you're also going to be using this sentence to describe how many equal parts the whole has. Now in the last lesson I did remind you that you are going to need a pencil or pen and a ruler and a piece of paper for this lesson. So if you haven't got those things already perhaps you'd like to pause the video now and you can go away and get yourself ready for learning and then start the video again when you are, thank you. How did you get on with the practise activity that I set to at the end of last lesson? Did anyone manage to find a whole that was even larger than Europe? How about this? Did anyone come up with this? And what about even this, the solar system, that was as large as I could think of. Okay, so have we got our equipment ready? So this picture is one part of a whole. Can anyone remember the name of this shape? Altogether, it's an equilateral triangle. Well remembered. So what I'd like you to do is I'd now like you to draw me the whole. Why are you not all drawing at the moment? Ah, do you need some extra information to be able to help you to draw the whole. Would it help you if I were to let you know that the whole has four equal parts, so each of those parts is going to look exactly like this. Would that help you? So now would you like to have a go at drawing me what you think my whole looks like? As you know, Mr. Ted is always really keen to give it a go in his maths. He thinks the whole might look like this. Do you agree with him? Or do you disagree? What do you think? Oh, there seem to be quite a few people that are actually disagreeing with him. Yeah, I think I am on your side. I disagree with him, but can you explain to him and maybe to your own Teddy as well, why it is that you think he's not drawn the whole correctly? So let's think about it. It says that the the whole has four equal parts. Now I can see that he's drawn the same shape each time so he's kept the parts equal, but has he drawn four of those parts? Let's just count. One, two, oh dear. That's where he's gone wrong. Maybe you and he can learn from that mistake. So I'd now let you to have a go. Best thing is to pause the video while you're doing the drawing and then you can show your whole to someone else in your house or even your Teddy. Don't forget the mistake that Mr. Ted made. So you do need to remember that your whole has four equal parts and maybe you'd like to challenge yourself. Do you think you can come up with more than one whole that this shape could be a part of? Maybe you see how many different wholes you can draw. So, do your wholes look anything like any of these? Oh, what's that Mr. Ted? Mr. Ted thinks he spotted an error or maybe he's learned from his mistake. Why don't we use this sentence and see whether we can check each of these drawings and see which one is incorrect. So let's have a look at this one. The whole has four equal parts. Yes, so that one's correct. Let's have a look at this one. The whole has four equal parts, so that's correct too. Let's have a look at this one. The whole has four equal parts, so that's also correct. Do you want to do this one on your own? The whole has. So that one's correct. So that must mean, ah, how many equal parts has this whole got? Let's count them together. One, two, three. The whole has only got three equal parts. So Mr. Ted, well spotted. He's obviously learned from his error and he spotted that that one's incorrect, excellent. Did you spot that too? So this time the triangle is a part of a whole that has three equal parts and I'd like you to see if you can draw what you think that hole is going to look like. So again, if you'd like to pause the video while you're drawing and then maybe show it to someone in your house, if they're available, or alternatively, you can show it to your Teddy and then start the video again. Okay, so this is what I drew. Does your whole look anything like mine? It might look different. It might look the same, but the way that we can check that it's correct is to use this sentence below. Has your whole got three equal parts? Just double check and then we'll say it altogether. The whole has three equal parts. Excellent. So we're now going to look at a whole that's made up of different shape parts. Here it is. Can anyone remember the name of this shape? Let's say it altogether. It's a rhombus. Well remembered. Now what I'm going to do is I'm going to draw some wholes that could be made up of this part and I'd like you to use this sentence to describe the wholes that the part is made up of. Okay, so here's the first one. Are you ready? Let's say it all together. The rhombus is one part of a whole that has one, two, three equal parts. Well done. Now let's see if you can spot the next one. We say it all together. The rhombus is one part of a whole that has three equal parts again. And the next one. The rhombus is one part of a whole that has three equal parts. And finally, here's another one. You say it this time. The rhombus is one part of a whole that has. That's correct, it has three equal parts. So all of these wholes had three equal parts. So we could say that if the whole has been divided into three equal parts, then one, two, three of those parts make one whole. Let's say that together for the next shape. If the whole has been divided into three equal parts then one, two, three of those parts make one whole. Let's do the next one. If the whole has been divided into three equal parts then three of those parts make one whole. And finally, you have a go on your own this time. If the whole has been divided into three equal parts, then. Well done. Three of those parts make one whole. Okay, so who's ready for a challenge? Now I need you to be the teacher now. And what I'd like you to do is to mark these children's work because what they've been given is a part, and you can see the shape of the part, and they've been told that that part is one part of a whole. And they've also been told that the whole has three equal parts. So you can see that they've all drawn a different whole. But my question is, which ones are correct and which ones are incorrect? And if they've got it wrong can you explain to them where they went wrong as well? Now I suggest that you pause the video, have a think about this and if you can find someone in your family to tell them what you think or alternatively, you could always tell your Teddy, do that and then come back to the video after you've done that. Okay, are we ready to find out how we got on? So let's have a look at Max first. Now this is quite a difficult one and it might help, what if I were to draw that on, because then it shows you the parts he's used to create that whole shape. Now let's check. Has he used the correct shape part? Yes, it's definitely all equal and it looks the right shape. But how many of those parts has he used in his whole? One, two, three, four, oh dear. Max has got that one wrong, hasn't he? Now let's have a look at Beth. What do we think about Beth? Well she's definitely got three equal parts there. So give her a tick. What about Ellen though, has she got three equal parts? She's definitely got three parts. Are they equal? Look closely. Yes, they are, aren't they? And then finally let's have a look at Florent. So we've got three parts but what do you notice about the shape of those parts? Do they match the original part that was given? No, they don't. So I'm afraid that one's wrong too. To finish this lesson, we're going to go back to the original slide that I showed you. Remember I told you that this was one part of a whole and I asked you to draw what the whole could look like. Initially, you couldn't do it, could you? Because I hadn't given you enough information about how many parts were in the whole and whether the parts were equal or unequal. So now what I'd like you to do is just imagine if I told you that this is one part but the whole is made up of unequal parts. What might you draw then? Here's some of my ideas to get you started. You can see that each whole does contain that triangle as a part but that the parts are unequal. And actually, each of my wholes has got a different number of parts in it. I bet you can come up with some really good ones yourself. So what I'd like you to do for your practise activity is before the next lesson, have a go at drawing what some of these wholes could be and the each drawing that you do, can you also say and write the sentence below? So the whole is made up of how many unequal parts. Remember they do need to be unequal. Hope you enjoy doing that and see you soon. Bye.

In this lesson, we will work out how many equal and unequal parts the whole has and if we can build a whole once we know a part.

In this lesson, we will work out how many equal and unequal parts the whole has and if we can build a whole once we know a 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

Build 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

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

Lesson overview:Build a whole when a part is known

Core Content

Fractions: parts and wholes: