Lesson video

Hi everyone, and welcome to a science lesson with me, Miss Emms. I'm feeling very excited about this lesson.

I hope you all too.

And I hope you've managed before this lesson to have a look at the first two lessons of this science unit.

Before we start thinking about this lesson, if you have, let us get started straight away and go to our slide show.

So in today's lesson, we're going to be answering the key question, "Which material is the stretchiest?" And we're going to be thinking a lot about that term, stretchy.

And again, just to repeat, this is a lesson with me, Miss Emms. Okay, let's begin.

So, first things first, we're going to go through our star words, and then we're going to answer some recap questions.

And after that, we're going to start thinking about this key word of today's lesson, elasticity.

Can you say elasticity? It's quite hard to say, isn't it? You did a really good job.

Then we're going to investigate and compare elasticity.

And after that you will have an end of lesson quiz.

So let's get started.

You're going to need the following things for this lesson.

You're going to need an exercise book or paper, you will need a pencil and you'll need your brain switched on ready to do lots of learning.

Can you give your brain a tiny little rub like this? Amazing, well done.

And if you've got these things, it would be great if you could also find a cloth or a piece of clothing, a plastic bag, an elastic band, or a hairband and a piece of paper.

Don't worry at all if you haven't got all of those things, ask your parents or carer, if you're allowed to find what you can from those.

And don't worry about finding things that you haven't got.

Just bring what you have got to where you're doing your lesson.

And don't forget your paper, pencil, exercise book paper, pencil as well.

So pause the video now and go and get yourself ready for the lesson by getting those things, pause now.

Fantastic, we're ready to start.

Let's have a think about our star words, you ready? Star words, star words, star words.

Stretchy, your turn, stretchy.

I might say that this sock is quite stretchy.

Stretchy, your turn.

Right, elasticity, elasticity.

That's tricky word to say, let's break it down.

Elasticity, your turn.

Right, if something is elastic, that means it's quite stretchy and it can return to its original shape once it's stretched.

But don't worry too much about the definition of elasticity.

We're going to come to that very soon in the lesson.

The next one is measure, measure.

You probably have heard the word measure before.

We're going to measure and compare elasticity in our investigation today.

Measure, your turn, amazing.

Material, this object is a water glass.

The material is glass, it's made of glass material.

Compare, your turn.

When you compare two things you look two or more things, you look at those things and you evaluate.

So when we compare elasticity, we're going to compare how elastic, how stretchy the sock is compared to for example, a piece of clothing.

Compare, and lastly stretch, your turn.

Can you give me a full body stretch, stretch, your turn.

Well done, amazing.

Well, I wonder if a stretch made you feel a bit sleepy, maybe you did a little yawn, stretch, your turn, right.

Okay, a quick recap slide, what were the four ways of changing the shape of solid objects that we learned? We learned four ways that you can change the shape of solid objects, I'm going to give you a clue.

One of them was squashing, pushing down, squashing.

What were the other three? Pause the video and tell your screen.

Did you manage to get it? We have squashing, pushing down, we had bending, we had twisting, and we had stretching.

Squashing, bending, twisting, stretching.

Can you do all four in a row like me, ready? Squashing, bending, twisting, stretching.

Well done, everyone.

So, this keyword, elasticity, your turn.

Elasticity.

I'll say, elasticity.

So, elasticity, it is a measure of how elastic something is.

It means something similar to stretchiness, stretchiness.

Okay, they have a slightly different meaning, but first of all, can you think of a material, any material that you could stretch.

Tell your screen, maybe you can think of two, tell your screen.

Hmm, lots of great ideas, I can stretch this sock.

I can stretch this and that elastic band, these materials I can stretch, they are quite stretchy.

So, elasticity has a similar meaning to stretchiness, okay? The difference is that elasticity, refers to how to, so when you stretch a material or an object like this, can it regain its original shape? So if an item, if a material has a high elasticity, that means it will quickly go back to its original shape.

This elastic band has a very high elasticity.

It's very elastic, it's very? And that means it will quickly return to its original shape.

If I let go, it returns to its original shape.

I can stretch it quite far.

And if I let go, it will return very quickly to its original shape.

It has a really high elasticity, or you could say it's really elastic.

And that's probably why it's called an elastic band.

So today we're going to have a think about different materials and their elasticity.

So elasticity is the ability of a material to return to its original shape after it's been scratched.

So you stretch it, and if it can return to its original shape after it's been stretched, it has a high elasticity, okay? Or it is very elastic.

I want you to tell your screen now, what is elasticity? Start with the ability of a material to, elasticity is? Go, pause and tell your screen, I'm listening.

Right, elasticity is the ability of a material to return to its original shape after it has been stretched.

And so it's got high elasticity, 'cause it can return to its original shape.

I want you to make some predictions now, and you're going either, you can just do this to yourself, to your screen pointing and maybe saying thumbs up or down, or you can draw these items and you can tick or cross next to them.

Do you think an elastic band is elastic? Do you think that can be stretched and return to its original shape? What about a jumper? What about a table? What about a cloth? What about paper? And what about a plastic bag? I would like you to pause the video, to draw these items on your piece of paper, to tick if you think they are elastic and to cross over them, if you think they are not.

Off you go, pause now.

Right, well done everybody.

We're not going to go through those yet because we're going to do a bit of an experiment soon where we investigate elasticity.

but I can tell you that you would have got a cross for the table.

I wonder what you've got for paper? We're going to have a think about that, but you definitely would have got a cross for the table.

I am sitting at the table now and I could not stretch the table if I tried to.

Okay, let's have a think now about investigating and comparing elasticity.

We are going to use these keywords, measure, your turn.

Measure, and compare, compare.

So we're going to think about measuring elasticity, seeing how elastic different things are, and comparing their elasticity.

So you can measure the plasticity of just one item.

But when you compare, you're looking at more than one, you're looking at more than one.

Okay, so I'm going to get these things ready, and I've got them in front of me.

I've got, I said a cloth or piece of clothing.

I'm going to use a piece of clothing, but you might have a cloth.

Don't worry if you haven't got any of these, you can watch me do it.

I've got an elastic band or a hair band, so I've actually got an elastic band here.

I've got a hair band to tie up my head.

I'm going to use the elastic band, a piece of paper, a piece of paper and a plastic bag, a plastic bag, okay? Can you pause the video now? And if you've got these items in your house or even a few of them, can you go and get them now? Pause and do that now.

Right, well done everyone.

So, what I'd like you to do is you're going to draw.

You're going to write the title elasticity on a piece of paper and you're going to draw it and write least stretchy and stretchiest at the other side.

So on the left-hand side, least stretchy, and on the other side, the right hand side, stretchiest.

Can you pause the video and just draw your line with those labels and arrows now.

Don't worry about drawing this part here, off you go.

Right, well done.

And you are going, what are you going to do is you're going to investigate how elastic these items are, and you're going to organise them from least stretchy to stretchiest.

So you're going to draw or write or you can do both.

So if you investigate, so you're going to have to have all four of them and test them against each other.

So let's do the first one together.

I'm going to think about the cloth or clothing and my elastic band.

So first of all, I'm just going to compare those two.

You're going to have to compare each combination of two against each other.

So here's my piece of clothing.

And they're not the same size, but I can still get a sense of how elastic they are, and here's my elastic band.

So when I stretch the elastic band, I can put it really far and it will go back to its original shape.

Look how far I can stretch it, that's really elastic.

That has a very high elasticity, it's really stretchy.

If I take a piece of my clothing, so I'm taking the sleeve.

I can pull it a little bit.

So it does have some elasticity, it is a little bit elastic, but not very much, okay? So when I'm comparing these two, the elastic band is going to go farther to the stretchiest side of my line.

I've done the first two, but you are going to have to position all four of these items. So comparing the clothing or cloth, the elastic band or hairband, the piece of paper and the plastic bag.

Can you pause the video now and complete your investigation? Good luck, pause now.

Fantastic, I wonder what you found.

Let's have a look.

So, you probably found that your paper was the least stretchy, I don't know about you.

But I couldn't stretch my paper too.

If I tried really hard, either my hand just moves off or I might be able to tear it.

I might have to do this to tear it, but it's not elastic.

The plastic bag had a little bit of elasticity, but then actually mine, I don't know about yours.

Mine if I stretch it, look, it doesn't return to its original shape.

I can stretch it, but it is steady, stretched, it doesn't return to its original shape.

So it has very low elasticity, okay? It's not elastic really because it doesn't return to its original shape, it can be stretched a bit.

So that's why I put it as higher than paper.

Then I would have my cloth or my clothing because as we saw, I can stretch that a bit.

And it does return to its original shape.

I wouldn't want to stretch it too much because it might eventually get bigger, and it wouldn't fit me.

And then I had my elastic band, which had a really high elasticity.

If you need to perhaps tick or move things around on your sheets of paper, then you can do so now.

Pause the video, if you need to.

Okay, the next thing you're going to do is your end of lesson quiz.

You've done such a good job today, I'm so impressed with all of your hard learning.

Let's give ourselves another rainbow clap.

So it goes like this.

Your turn, well done, and I will see you next time.

Bye everybody, see you next time.