﻿Hello, everyone. It's me Mr. C, how are you all today? Ready for lesson number five, I hope, of our shape and symmetry. Let's move straight on, we've lots to do today and all real nice fun activities. So let's move on with that, shall we? You know exactly what I'm going to say next. If you haven't done it, go and take our Knowledge Quiz, and then come on back. Cause we miss you when you're not here. Okay, so are you ready? Are you ready for today's random world record? It's a good one. Get ready for the picture. Here it is. This is Puggy. Now Puggy is a Pekingese, a pekingese dog, and Puggy possesses the longest as they like to call it in licker Guinness world records, the longest licker on record has the longest tongue on record, over 12 cm. Now 12 cm is about that. I kind of begin to imagine how much tongue... I couldn't stick my tongue out that far, but that's the cutest little picture, but it's worth knowing that a Pekingese is actually a really small dog. So it almost looks like that tongue's about a third of the length of that dog's body. And that measurement was taken in a vet's clinic in 2009 when Puggy was nine years old. So I think Puggy may no longer be with us and there could be another dog out there that has beaten that record, but imagine getting a big old wet slobbery lickery kiss from Puggy with a tongue` like that you need one heck of a good wash afterwards, hey. That's a quite a licky dog. So let's move on to thinking about what we might need for today's lesson. So we're going to be needing a pencil, a ruler, and something to work on and somewhere quiet with no distractions and no wet lickery kisses from dogs with gigantic dog tongues. All right, so we see what the agenda is for today then. Well, we've our done Knowledge quiz, you've been given a random fact and now we're going to move on in a moment to our key learning and our key vocabulary. Then we're going to do a magic squares warmup, and I love stuff like this. I'm quite excited to share it with you. Then we're going to recap really quickly on all types of angles that we've covered so far, I'm getting a variety of different angle activities with the final knowledge quiz at the end. So let's see what our learning is today. It's the same objective really as yesterday to identify angles within shapes, but we'll look at some other things to do with angles as well. So our words are, and we can do them together today because we've practised in plenty of time so far in these sessions. Angle, degree, acute, obtuse, right angle, order, compare, 90 degrees and 180 degrees. Good job guys, so moving ahead. So this is just an example that I'm going to go through with you, this is what a magic square might look like. And this is a smaller one, a simpler one that I want to use as an example, simple one for me. Cause I know you can do the more advanced ones, but in a magic square when you feel it in, every row, every column and the two diagonals should add up to the same. And in this case, you've been told what they need to add up to. Here they all need to add up to a total of 15. So let me just help you out with where I would start here. There is one really obvious place. Remember, they've all got to equal 15 and I'm going to pop that in, and the same here and the same here. There, there, duh, duh, duh, and also going down. But there's one really obvious place to start. One place where I only need to fill in one last missing piece of information. And that would be there. I know that this plus these two numbers give me 15. So I'm just going to say to myself straight here: what's five add three, oh, eight. What do I add to eight to make 15? If I'm not sure. Subtract eight from 15. You should get a seven, seven, eight, nine, 10, and five is 15. So now I filled out one in. Oh, it gives me a hand somewhere else. Where else do I only need to now put in one number to help me complete? Two options actually. Don't forget the diagonals. So I could go here or I could look at this one. Seven add two gives me what? Yeah, seven, eight, nine. Gives me nine. What do I need to add to nine to make 15? Cause don't forget the columns have to make 15 as well. So nine, 10, 11, 12, 13, 14, six. I need to add another six. Now I know that this and this add this, also needs to give me 15, so I can fill in this number or this one. So six add five gives me 11, 11 add what makes 15? And then let's go here, two add five, seven. Seven add what makes 15? Eight? Let's check, eight, nine, 10, 11, 12, 13, 14, 15. Oh, that makes 15. So then we can fill in what's missing. Four add two gives me six. What do I add to six to make 15? Not sure, so how could I work out? I could take six away from 15. So 15, 14, 13, 12, 11, 10, nine. So nine must go here. Nine add five gives me 14. 14 add what gives me 15? 14 add one gives me 15. Eight add one is nine, nine add six is 15. Oh, look at that. Everything adds up to 15. So you need to find the first place to start. And these are yours. So these are trickier. Spend some time on this. Don't rush it, okay? Cause they're good things to start with. And I would say for both of them, start here and with this one. Now in this one, everything must make 34. Let me write it here to remind you. And then this one, everything must make 102, so much trickier. I would say, give yourself a good 10 to 15 minutes on this to really get your brains going. Okay? Don't forget. Look for the bits that are going to make it easier. Look for where you've got the least information missing. So we've already said haven't we, that to start with here is a good place to start. And so is here because that's where you've got the least information missing. When I fill this one in, I would probably look at that diagonal, same here, I'd look, okay, I filled this one in, where could I go next? Oh look, here's one with just one bit missing and then this one, oh look, here's one with just one bit missing. So always look for the one with the least digits missing. Give it a good go. Don't be afraid to make mistakes. It's the first time we've done something like this properly, but there are bigger numbers and much more logical thinking. Do it lightly in pencil. If you make a mistake, it's not a big deal. Give it a really good go. I know you can do this. So just spend a bit of time working through it. Don't forget. I've given you tips on where to start and what the total should be for each of them. So don't forget on this one it's 34, every row is 34, every column is 34 and the two diagonals here and here are also 34. So in this one, they're all 102. I have so much faith in you guys. I know you can do this so best of luck and I'll see you back when you've given it a go and ready to move on in five, four, three, two, one. And let's move on and find out those answers. So here you are Here are the answers that you needed. The ones remember that I told you to start with. They certainly helped me when I was doing it. So this one and this one, they were the big helps. And then from here I went to the missing one there. Then I went here and I kind of bounced around all over it Cause then I could do the top one and so on. It's almost like a game of dominoes, where you get one and everything else falls into place. And then it's just a case of, I think in subtracting. So, massive well done. If you got those right, you are my mathematical heroes. So good job. Let's see what's coming up next then. Here are the activities then. We're going to start off by sorting angles. Now we've looked at three types of angles. I wonder if you can remind me what they are, what angle, what type of angle is exactly 90 degrees? What kind of angle is exactly 90 degrees? It's a right angle, well done. What kind of angle is bigger than 90 degrees, but less than 180? Yeah, that's an obtuse angle. So the one that's less than 90 degrees, the cute little angle, click with a mouse, that's an? Yeah, an acute angle. So for each of the angles that you see on the screen, we're going to code them. You're going to write A next to it, if it's an acute angle, you're going to write R next to it, if it's a right angle and you can to write O, next to it, if it's an obtuse angle. Makes sense, right? And when you find the right angles, can you represent them in the correct way? Have a go and see. I'm back in five, four, three, two, one. Let's go, shall we? All right. So here we are. First angle there then, was an acute angle. And let me just remind you about something that we were looking at earlier this week, and it's kind of related to here. Do you remember this? So we had our different types of angles on there and it's a really nice way of remembering it. We all want things out of the way we hide at the bottom here, here and here, we had our right angles. At the top we had one that was less than 90 degrees. So that means it's an acute angle. And then here we had one much bigger than 90 degrees, which means it's an obtuse angle. And I just kind of have that. In fact, I had it stuck above the computer here on the wall, so I could see it. Just to remind me of what each of those angles might look like. So this would be really useful. And I can actually see that the first one at the top on that grid that you've just looked at. It's very similar to this angle. So that helped me to recognise that that was in fact, an acute angle. All right, now for my waffle. Let's just look closely at some of the rest of them then. So A was acute, B was obtuse, C was a right angle. So it wasn't quite indicated properly. Don't forget on a right angle we need to have our marks to show that. That's my right angle. D was an acute ankle. E was obtuse. F was obtuse. G was a right angle. So let's get that in there. Let's always be professional with our mathematics. A was acute less than 90 degrees. This one was acute, so our final and I was a right angle and let's mark it off like so. Yours would have been much, much, much, much, much, much neater than mine. Technology doesn't always help. So we can see clearly what kind of angles they were. So you should have had three obtuse, three acute and three right angles. All right, good work guys. So here, we're going to do it again. We're spotting the angle and I need you to label as many as you can. Remember, an angle is anywhere that two lines meet or cross. If the two lines crossed and I'm creating several angles, you see? I've got one on top, bottom and either side. So wherever lines meet or what we call intersect, they will create angles. So this image that we have here, full of different angles, so many different ones in there. So within that box, how many can you find? And how many can you label? So A for acute. O for obtuse and R for right angle. Mine done. Go for it. Spend a bit of time going through and seeing how many you can label. You might also notice that we've got a lot of triangles in there. Can you spot any other shapes that are not triangles? little additional challenge for you there. So give it a go. Jot them down. When you are ready, come back and join us and we'll see you soon. I'm back, all right. Let's take a look, shall we? I know I've not marked them all. Well, 'cause there were a lot on there. And I don't want to put letters everywhere to confuse you when you're looking between yours and mine. But here are a few that I managed to find some are right angle here and I'm going to be super, super effective. There's another right angle. Right angle is how many degrees? Yeap, 90. I've got some acute angles here. Acute angles are less than? Mm-mmh, 90 and more than? Yeah, 0. And there are obtuse angles here, much much bigger than 90 degrees, but less than? Amazing, 180. Let's just look at a couple of others. What about this one if I mark off this angle here? That would be acute. What about... Oh, this one, big clue. A right angle. That one? Yeah, obtuse. We've got some right angles on the other side here. We've got another one down here. What about this one? Yeah, obtuse. And so on. You've got a picture. I wonder if you spotted any other shapes that weren't triangles? What about for example, this one here? One, two, three, four sides. It's a quadrilateral. It's just irregular. What about this one? One, two, three, four, five sides. So you have a Pentagon, a little lots of various different shapes there. We've got so many different types of triangles. I wonder if you can spot how many there are all together. All right. So moving on then. Have a look at this. Here's our angle quiz. Two questions there for you. Question number one: Order do these angles from the smallest to the largest. And you can label them one to four. So for example, if I thought this was the smallest, I would call that number one. So one is the smallest, four is the largest. Now in the second question, you've got three shapes, shape A, B and C. I'm asking you, which is the odd one out, based on its angles and why? Now, it could be any particular answer. As long as you can back it up with evidence. Remember in our last session, we looked at a bit of evidence. Sometimes always, never have a go here. And remember, evidence is something that you can use to prove a theory in maths. So if you think something is true, you need to be able to prove it, okay? So that's why we're using evidence. This is the same as if you're doing a reading comprehension, you would give evidence from the text. Well here, we're going to give evidence from the maps that we can see in front of us. So have a go at answering those questions and come back to us when you're ready. We're back. All right. So we say then, so number one here, clearly the smallest was this one. So this is an acute angle. The second one up was this one, also acute. What about number three? Yeap, right angle. And number four? Obtuse. Okay, brilliant. Now what about this next one? Couple of different answers I'm going to give to you. I'm going to say, first of all, that shape is based only on its angles remember, and not to do with number of sides or anything like that. Just the angles. So I could say that shape C was the odd one out because of its angles, because it's the only one that has a certain type of angle. Shape C is the only one that has any right angles. In fact, it has only right angles. So I could use that. So I could say, shape C is the odd one out, because it's the only one that has right angles. I could say that shape B is the odd one out. And I could say, for example, because it's the only one that has acute angles. I could say that shape A was the odd one out because it was the only one that had only... Yeah, you got it. Only obtuse angles. So I've used evidence and argued for each, so they could, in fact, all have been the odd one out. There was no real sort of right or wrong answer about which one you chose. It was just about what your reasons were. So let's have a look at one final, little bit of challenge here from me. Look at the shape that I've drawn and you're going to use the less than and greater than symbols to make the statements correct. There are four angles on there on my shape. A shape has four sides. So what kind of shape is that? Yeah, it's a quadrilateral. So I've got angle A right here. Angle B, angle C and angle D your job is to use less than, and greater than to make these statements correct. Now, if you forget how to remember that, I'm not going to go down the route of crocodiles because that, no, not in here. We don't need to talk about crocodiles. But what I will say is that the symbol will point to the smaller number. So the smaller number will be on this side. So here's my smaller number. I'm always pointing to the smaller number basically. It was a weird little dance I did. We've done a few of those over the last few sessions. Maybe angles are not great for keeping me still. So give it a go and fill in the missing symbols. Shall we see? So angle A is less than angle D. Angle B is greater than angle D. Can you see that? Angle B is greater than angle D. Good. Angle C is less than or smaller than angle D and angle A is? Perfection. Less than angle B. Wow guys, what great work there. You nailed it with that. So you know what I'm going to say. Right at the end now almost. So go away. Don't go away, but you know what I mean. Go and do your Knowledge Quiz and I'm coming back as soon as you have completed that, and I'll see you very very shortly. All right, welcome back. Well, that was the end of session five of our shape and symmetry. And we've covered a lot this week. Remember, let's just recap. The main types of angles that we're looking at, there were four mentioned, three main ones. And I wonder if you can remember the fourth one. So the smallest type of angle, which is less than 90 degrees, but greater than one degree, greater than 0 degrees, so one degree upwards is an? Acute angle. Exactly 90 degrees is a? Yeap, right angle. Greater than 90 degrees, but less than 180 degrees is an? Obtuse angle. And the last one we mentioned right back at the beginning of these sessions was? Oh, good memory if you manage to remember a reflex angle. Well done. The other one we've mentioned was the straight angle, which was 180 degrees. That's two right angles. Guys, you've done so much this week. You've made angle measures. You've made these l... What's it? Someone come up with a great name for this? Cause I can't think of one. And you've learned a lot. You've put it into practise and you've proved what you've found. You've talked about your theories and you've managed to backup your evidence. So I'm really really happy with how things have gone this week. You guys have been phenomenal. So have a wonderful rest of the day. I look forward to seeing you very very soon. From me, Mr. C, that is also signing off. 'Adios and chow.'

In this lesson, you will recap on the names of different types of angles.

Maths

Y4 Maths

Key Stage 2

Year 4

Shape and symmetry:Identify angles within shapes

2-D Shape and Symmetry 

Geometry

THEME

UNIT

Shape and symmetry: To compare and order angles

Shape and symmetry: To identify right angles

Shape and symmetry: To identify acute and obtuse angles

Shape and symmetry: To investigate angles within shapes

To compare and classify 2D shapes

To compare and classify quadrilaterals

To identify and classify right angled and equilateral triangles

To Compare and Classify Isosceles and Scalene Triangles

Quadrilateral Problems

To identify lines of symmetry in 2-D shapes

To identify lines of symmetry in a pattern

To complete a simple symmetrical figure

To investigate a problem using symmetry (Part 1)

To investigate a problem using symmetry (Part 2)

Lesson overview: Shape and symmetry:Identify angles within shapes

Intro Quiz

Video

Presentation

Worksheet

Exit Quiz

Transcript

15 lessons in 2-D Shape and Symmetry :