What does the 'd' in 2-d shapes stand for?

Which of the shapes below is NOT a quadrilateral?

What is the name for a 2-d shape with 6 sides?

A shape where all sides and angles measure the same

Comparing & classifying 2-d shapes

Key Stage 2

Maths

2-D shape, perimeter and area

What is the perimeter of the shape below?

﻿Hi there welcome to this lesson on 2-D shapes my name is miss Darwish, but if you prefer to call me Miss D then that is absolutely fine. First of all, before we get started with the lesson, I just want to check on two things. If you do have a mobile phone, then if you could just turn it off and put it away just to avoid any distractions and the second thing is just to make sure you are basically sat in a nice quiet environment, ready to start the lesson. So for today's lesson, we're going to be looking at what a 2-D shape is. And once you've had a look at some examples and non-examples of 2-D shapes, we're then going to have a look at sides and vertices of the 2-D shape and also angles and parallel lines of the 2-D shape. And once we've covered all of that, of course at the end there is a quiz for you to do. So let's get started, so you will need a pencil and something to write on paper, notepad, whatever you've got handy. Okay, so when we look at 2-D shapes, I've shown you three examples on the slide. So these are what we we'd call 2-D shapes, Now the letter D in 2-D shapes actually stands for something, do you know what it stands for? So it stands for two dimensional shapes, so the D stands for the word dimensional. Well done, if you knew that. Okay, we're going to have a look at some examples of 2-D shapes. So we've got four examples of 2-D shapes, shapes that you would have seen before, okay. And I'll talk to you about why these are all 2-D shapes, first of all, I'm just going to move myself out of the way, and we're going to have them look at some non-examples, shapes that are not 2-D shapes. So can you see the three examples of shapes that are not 2-D shapes? Can you see what's the same and what's different between the examples and the non-examples? So on the examples of 2-D shapes, each shape has a width and a length only. So a 2-D shape is a flat shape with a width and a length. The non-examples do not show flat shapes, can you see that? Okay, now we're going to have a look at a hexagon, so hopefully you might have seen a hexagon before. Can you see how many sides the hexagon's got? Let's count them together, there are six sides let's see, One, two, three, four, five, and six. Okay now we're going to have a look at a pentagon. I want you to tell me this time how many sizes of pentagon have and show me on your fingers again I'll just move myself out of the way. Once you've counted the sides of the pentagon show me on your fingers. Okay, let's count these together, see if you were right, one, two, three, four, and five. So pentagon is a shape with five sides well done. So remember, a hexagon is a 2-D shape with six sides and a pentagon is a 2-D shape with five sides. Well done. Okay, now we're going to have them look at what a vertice is. You've probably heard of it before when we've talked or spoken about shapes. So we're going to have a look at, what shape is this? It is a hexagon, how do we know? Because it has six sides, well done. Now we want to look at the vertices, so let's start off and talk what is a vertice? When we've got to talk about one vertice.. we say one vertex or many vertices, so I'm just going to show you what that is, where the two sides of any shape come in, they form a point and that point is basically called a vertex, one vertex or many vertices. So let's have a look, a hexagon, as we know from before has six sides and it also has six vertices. What about a pentagon? How many sides and how many vertices does a pentagon have? Again show me on your fingers. So how many sides does a pentagon have? show me your fingers. Five and how many vertices is a pentagon have? Have you counted them? Let's see, also has five vertices well done. So again, where two sides of shape meet that is called a vertex or vertices when there's lots. Okay. Now you can see five shapes and I've named these A, B, C, D, and E. So these are shapes that you may have recognise or see that you may recognise or have seen before. What I want you to do is write down on your note, the piece of paper, the letters of the shapes that have only five vertices. So you go through each shape, write down the letters of the shapes, closing the question shapes within one, which ones have got five vertices? Okay. If you want to press pause now you can, otherwise we'll have a look at shape A together. How many vertices the shape A have? It's only got four vertices, so it's not that one. What about shape B? How many vertices the shape be have? Just three, so it's not A and it's not B. What about C? How many vertices to C have? I counted to five, how many did you count? So it's C, let's check the other two shapes though. What about D how many vertices does shape D have? I counted five. So it's also shaped D and what about shape E? How many vertices does shape E have? Also five, so hopefully you had shapes C, D and E all have five vertices. They look different, but they've all got five vertices. Okay so, so far we've looked at, we've spoken about sides and vertices of shapes. So when we group shapes, we can talk about the number of sides they have and also the number of vertices that they have. What else can we talk about when we're tryna compare and group shapes? Apart from sides and vertices, can you think of anything else? If you can, jot these down for me? Okay. So we can also talk about angles, when speak about shapes and lines, the type of lines that each shape path. So when we spoke about angles, sometimes we say this shape has got a right angle and that means an angle that is 90 degrees, this is how I like to... So an angle you can see that is 90 degrees. And if the angle is smaller than 90 degrees, it's small, it's cute, it's small that's how I think of it. An acute angle is an angle that is less or smaller than 90 degrees. So I always remember because it's smaller, it's quite cute. So it's an acute angle. Okay. And the type of lines that they have, so the lines I've just showing you before, when we extend them, they will never, ever, ever touch. Okay, so they're two lines that keep following on together, as you can see, and they never meet, they never touch. So now let's have a look at angles and lines when it comes to 2-D shapes. So I've got some quadrilaterals for you, so we starts off with a rectangle. How many sides does a rectangle have? All done, And how many vertices dose a rectangle have? Also four. Now the next shape we're going to have a look at is called a parallelogram. Can you say that word for me? Parallelogram, well done. How many sides can you see in the parallelogram? Four well done and how many vertices can you see? Also four, so it's same as the rectangle. Okay. And we've got another rectangle, it looks a bit different, but it's still a rectangle it has four sides and four vertices. And then the last shape we're going to have a look at is a trapezium, can you say that word trapezium. And how many sides is the trapezium have? Four. And how many vertices? Four. Have you noticed how the number of sides seem to be the same as the number of vertices in the 2-D shapes? Okay. Now, I want you to point at the screen in front of you, which of these shapes have a right angles? So you've got two different rectangles, you've got a parallelogram and you've got trapezium, which of these shapes, can you spot any right angles? Just when you see it point at the screen. Okay. So both rectangles do have right angles as you can see, but the parallelogram and the trapezium, I can't see any 90 degree angles at all. So well done, if you said both rectangles. Okay, now we're going to have a look at some regular 2-D shapes. When we say the word regular, it means all of its sides are the same length. So I've got a square, an equilateral triangle and a regular hexagon. So these are all examples of regular 2-D shapes. Why they regular again? Because the width is the same length as the length. So if I measured the width with a ruler, it would be the same as the length. Now, which of these shapes can you spot any parallel lines? When the parallel lines, what're parallel lines again, say it to me, two lines that never ever meet. So when you keep extending these two lines, they never touch, okay? So which of these shapes? Let's have a look at the triangle first of all, are any of the sides not touching? No, the equilateral triangle definitely does not have any parallel lines at all. What about the square? Can you see the sides of the square? They never meet, and these sides they will never meet. So a square has two sets of parallel lines well done. And what about the regular hexagon? You see two of the sides if we extend them, they would never, ever meet. Well done. Okay. We look at properties of shapes now. So we've spoken about four different things when it comes to looking at shapes, we've spoken about the sides, we've spoken about the vertices, we've also spoken about angles, excuse me, and about parallel lines. Now, what we're going to do, is I'm going to talk about a right angled triangle and I'm going to say all facts about a right angled triangle. And once I've done that, it's then going to be your turn to do the same about a parallelogram. Are you ready? So a right angled triangle, it has three sides, a right angled triangle. It has three vertices, a right angled triangle, does not have any parallel lines and a right angled triangle, has one right angle, the clues in the name. Okay. Now what I'd like you to do is grab your pencil and your sheet of paper. And I want you to write down for me, I'll try and do this together. How many sides does your shape have? How many sides does a parallelogram have? Write it down for me, that's your first bullet point. So how many sides does a parallelogram have? Okay once you've done that, your second point, can you guess what I'm going to want you to do next? How many vertices does your parallelogram have? And write it down again. So how many vertices does your parallelogram have? Okay, third bullet point now is does your parallelogram have any parallel lines? Yes or no? Does your parallelogram clues in the name, have any parallel lines? And then the last bullet point, can you guess? Does your parallelogram have any right angles? Just zero right angles or one right angle or two right angles or four right angles? Does it have any right angles? Okay once you've done that, just check over your bullet points. So your first bullet point, you're telling me how many sides it has and then how many vertices. And then if it has any parallel lines, and then if it has any right angles and when you're ready, we can go through the answers together. So, it has four sides of course it has four vertices. My parallelogram has two pairs of parallel lines, that's why it's called a parallelogram by the way. And it does not have any rights angles, just want to say a massive well done, if you've got all of those four points. Okay I'm just going to move myself out of the way there. What type of angles does this shape have? So we just said that parallelogram does not have any right angles. So then what kind of angles does it have? What do you think? What kind of angle is this? Is it bigger or smaller than 90 degrees? Well done, it is smaller than 90 degrees, therefore it is an acute angle and actually it has two acute angles, can you see that? So the two angles marked there, are both acute angles, they are both smaller than 90 degrees. And then the two angles that are not marked on the parallelogram, are they larger or smaller than 90 degrees? They are larger than 90 degrees and do you know what we call an angle larger than 90 degrees? An obtuse angle, well done. Okay. Now I'd like you to pause the video to complete your task, you've got two independent tasks to complete. Once you have completed them, the you can press play again. Hi there hopefully you don't find those questions too difficult. We'll go through the answers to prep the independent tasks that I sent you. Okay so, for the first one, we'll look at the table. So the first check I asked you to look at was the right angled triangle. It has three sides of course, it also has three vertices, it does have one right angle and it does not have any parallel lines or parallel sides. Give yourself a nice big tick if you got that first row correct. Okay. The next part was slightly trickier because I told you some things about the shape, but what I didn't do is tell you what that shape was. Now, if this shape has four sides, four vertices, it also has four right angles and it has two pairs of parallel lines. This shape could either be a square, well done if he said square, or it could also be a rectangle. So well done if you said square, well done if you said rectangle and an extra, extra well done, if you said square and a rectangle, when you put both names in, but either one was fine. Okay and then the last part of the table, where's I had asked you to fill out some properties about a parallelogram. Now, if you remember, the parallelogram was the shape that you were describing back to me earlier in the lesson Do you remember? Okay, so of course a parallelogram has four sides and four vertices, it does not have any right angles and it has two pairs of parallel sides. I want you to give yourself an extra big tick if you got all of that table right? Okay. You ready to look at task two answers now? What I'm going to do, I'm just going to move my face out of the way 'cause it's covering the shape that we're looking at, there we go. Okay. My friend says this shape has seven sides and six vertices, is my friend right or wrong? Explain. So we can see the shape in blue. First of all, she said it has seven sides, does the shape have seven sides? Did you count them? I counted seven, so my friend is correct when she says that the shape has seven sides. What about vertices? Does the shape, have six vertices? How many vertices did you count? I counted seven as well, seven sides and seven vertices. So I can say that my friend is both right and wrong, you might have said she's correct and incorrect at the same time. There are seven sides, but there are also seven vertices. So she got the part about there being seven sides correct. But she made a mistake when she was counting the number of vertices. So well done if you got that correct again, give yourself a nice big tick. Okay, what I would like you to do if possible, I would love to see the work that you completed today. So if you can ask your parent or your carer to share your work on Twitter, you just need the #LearnwithOak and make sure to tag @OakNational. I would love to see your completed tables and I would also love to read your explanations that you wrote about my friend being correct and incorrect. So if you wouldn't mind sharing your work for me to see, that would be great. That's now the end of today's lesson before I leave you to go and complete the quiz, I just wanted to say a really big well done to all of the successful learning that you have completed today. So well done.

Comparing & classifying 2-d shapes

Comparing & classifying 2-d shapes

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UnitMaths / 2-D shape, perimeter and area

Maths