Lesson video

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In today's lesson, you are going to need the main things that we normally need.

A piece of paper, a pencil, a colouring pencil and a ruler.

However, at the end of the lesson, we are actually going to be making something.

So you might also need some extra materials but I'll explain that when we get to that part of the lesson.

You're also going to need your star words today.

Our star words today are light, shadow, reflection, lens, opaque and translucent.

Now all of these are words that we've come across already in our unit.

We know that light is a type of energy that travels in a straight line.

A shadow is an area of darkness that occurs when light is blocked by an object.

And we're going to revise shadows a little bit later in the lesson.

Reflection is when light, can you remember? I'm giving you the action.

When like bounces off an object.

We learned about lenses when we learned about the structure of the eye.

So a lens in your eye is the part of the eye that focuses light, but you could also have lenses and things like glasses and sunglasses.

And we're going to be looking at those today.

Opaque and translucent are two ways that we can describe materials.

I know pink material.

Can you remember, how much light does an opaque material let through? An opaque material doesn't let light through.

Well done if you remembered, what about a translucent material? A translucent material let some light through.

And what was the name of an object that lets all light through? Transparent, good job.

Okay, it's going to be important because some of the materials we're going to use at the end of our lesson to make fix, we're going to have to describe as opaque or translucent or why we're not using any transparent ones.

Actually, that's why that word is not there.

This is what we are going to do this lesson.

We're going to start with some quick recap.

Then we're going to learn about Periscopes, which are really cool invention.

And we're going to learn about different types of lenses.

Then we're going to revise shadows before we make our own shadow puppet theatres.

Okay, here's some recap.

Straight away, can you label the different colours of this rainbow? Pause the video and have a go for me now please.

Great, let's see if you remembered, even the tricky ones the bottom.

Give yourself a tick if you've got these right, if you didn't, no problem.

Just correct your answer, every time you correct a mistake, your brain grows a bit bigger.

Red was number one.

Number two was orange.

Number three was yellow.

Number four was green.

Number five was blue.

Number six was indigo.

And number seven was violet.

So indigo and violet are the tricky ones I sometimes forget.

I'm in that kind of bluey pathways.

Awesome, well done if you've got those correct.

Reflection, we looked at this in our car, in our car words.

That's weird, that's not something we use, in our star words.

So everybody please say the definition to your screen.

Reflection is when light bounces off an object, well done we've also learned about something else that can happen to light.

What was it called, what was happening to light when we did our investigation with our glass of water and our pencil? It also began with an R.

It was called refra, say it to your screen, refraction, good job.

Now refraction is when a light Wave changes direction.

Why does it change direction? Because it moves through to transparent objects, well done if you remembered that.

We're going to learn about the uses of the light today, but I bet you already know some of the things that we can use light for.

I would like you to have a go at writing some ideas on your piece of paper now please.

So pause the video and do that for me now.

Great, there are loads of things you could have written for this.

So we're not going to go through all of them, but you might have written some of the things that we use the light for in our homes like lamps or torches or your computer screen or your phone screen uses light.

Maybe you could have thought about some of the uses of light in nature.

So there's a particular type of organism that needs light to make its own food.

What type of organism is that? We showed you at the beginning.

Plants, so you might have written something about that.

We also use light to see.

So that could have been a big use that you wrote down.

And we're going to learn about a few more today.

Starting with Periscopes.

Periscopes are devices that can be used to see around objects, that would normally be in the way of something that we'd like to see.

So for example, if somebody would like to look around a wall or a corner in a corridor, but doesn't want to be seen themselves and they can't raise themselves up high enough to see over an object, a Periscope can be used.

So here's an example of when a Periscope is used.

This is a submarine, which is like a ship that goes under the water and Periscopes are very helpful for submarines because they allow the person inside the submarine to see what's happening above the surface of the water.

When the submarine is still inside the water.

This can be really helpful 'cause it means that the people in the submarine can check for objects or enemies and battle that may cause the submarine harm should they come to the surface.

So that's one example of when you might use a Periscope.

I'm going to show you a diagram now of what a Periscope looks like and how it works.

So this is our diagram.

So a Periscope involves using a long tube with mirrors placed at the top and the bottom.

So you can see on the diagram labelled a and a, those are two mirrors.

What do mirrors due to light? They re, re, re, they reflect light, okay.

So that's how we can use light in our Periscope to help us to see.

So, in fact, I'm just going to get my pointer up so I can point to the diagram and be really clear about what is going on here.

So you should now be able to see my squiggly red pointer.

So here, this is a mirror and this is a mirror.

Now, light enters the Periscope here.

It then reaches this mirror.

And what happens when it reaches the mirror? It reflects, it bounces off, so that's what's happening.

And then it travels down in a straight line, 'cause light always travels in a straight line, until it reaches the next mirror and then it reflects off.

What do you think c might be representing? What else do we need in order to see? We need our eyes, so c is representing our eye.

I would like everybody now to get their finger and to trace with me.

So what I might pointer, trace along your screen, how the light is travelling, okay.

So as my pointer moves, your finger is going to follow the pointer.

So light enters the Periscope, it hits the mirror and it reflects off the mirror.

It travels in a straight line till it reaches the second mirror.

And then it reflects off that mirror and into the eye.

It enters the eye through the pupil, the lens focuses it and then it hits the back of the eye, which remember is called the retina, okay, well done.

Okay, I'd like you please, to draw a version of this diagram, take your time.

You can just use a stick man to represent your observer, your person.

You need to draw your Periscope.

It needs to be thick enough so that you can draw some arrows in it and you need to draw your object that's being seen from the Periscope and the sun, okay.

So you need to draw this on your piece of paper.

And then what I'd like you to do is to add the arrows in, to show how the light is travelling.

So remember, it's always going to travel in a straight line.

So you need to use your ruler.

The first thing that you need to do, is you need to draw the arrow that shows light source to object.

Then it's going to, which is our flower in this case.

It's going to go sun to flower.

Then it's going to go flower into the Periscope.

Then think about how it travels within the Periscope.

Remember, we just trace that zigzag with our fingers on the last slide, and then it's going to go in to the eye.

So take your time drawing this diagram, it might take you a few minutes to make sure that it's really neat and you're probably going to want to draw it quite big so that you can fit your arrows in clearly.

Pause the video for me and complete that now please.

Great, let's see if your arrows look the same as mine.

So this is what it should look like.

So we have a source to object, object into Periscope, and then it bounces, it reflects on each of the mirrors in the Periscope and into the observer's eyes, good job.

No problem, if you made a mistake, just give yourself a star, a chance to correct that now.

Next, we're going to look at different types of lenses.

So we're not talking about the lens in our eye.

We're talking about lenses that we can make from glass, that actually help the lens inside our eye.

There are two types of lenses that we are going to learn about.

And they are called convex, my turn, convex and concave, Concave lenses.

Lenses are curved objects made from transparent materials, normally glass or sometimes a material called perspex, which is similar to glass.

And they come in to may and shapes, convex or concave.

The way to remember which is which, is that concave lenses curve inwards like the entrance to a cave, okay.

So have a look at the difference in the shape on the screen now.

The first type of lens we're going to look at is concave lenses.

So concave lenses help to spread light out.

This is helpful for some people who are, what we call short sighted.

Because in short sighted people, the lens in the cornea in the eyes are too strong.

So remember the lens and the cornea are what help us to focus light.

When we focused light, we toward that point.

So their lens and cornea are too strong.

So the light is too focused and they focus light two well for people to see properly.

So you can see in the top picture, the light is being focused too early.

It's actually not hitting the retina at the back, which helps us to see.

So short-sighted people need to wear glasses with concave lenses because it helps to spread the light out and so they can see better.

So this time, the image that they're seeing is focused at the back of the retina, where it's, where it needs to be.

Convex lenses do the opposite.

So convex lenses help to focus light onto a single point.

This is helpful for people who are long sighted because the lens and the cornea in the eyes of people who are long sighted is not as strong.

And so it doesn't focus light very well.

So long sighted people need convex lenses, which help them to focus the light better.

So this is how we can remember this, this is our sticky way.

Concave lenses are shaped like the opening to a cave.

So they're shaped like this, like a cave opening in a cave opening.

And they help short sighted people, because you have to be short to enter a cave.

That means convex lenses do the opposite.

So they're the ones that aren't shaped like a cave and they help long sighted people, okay.

So this is our sticky way of remembering.

Concave shapes like a cave and you have to be short to enter a cave.

So therefore short sighted people.

See if that will help you to answer the questions on the next slide.

So is lens A or B concave? Which group of people do convex lenses help? Is it short or long sighted? And which group of people do concave lenses help? Pause the video and have a go at answering these questions now please.

Great, let's see if you got those answers correct.

Lens B is the concave lens because it's shaped like a cave.

Long sighted people use, need convex lenses and short sighted people need concave lenses, because you have to be short to get into a a cave.

Well done.

Next, we are going to look at shadows.

We have learned what shadows are right at the beginning of these series of lessons but let's revise because it's been a long time.

So a shadow formed when an opaque object, like a tree, that doesn't let light through it, blocks the light and this course there's a dark area behind that object that's normally the same shape as that object, okay.

This happens cause light only travels in straight lines.

So it can't go round the tree.

You can't go through the tree because it's opaque.

So it gets blocked by the tree.

And we have an area where the light can't reach.

I have here on the left-hand side, a series of hand shapes, and these are used to make hand puppets.

So you might have done this before.

If not, then now's your chance.

I want you to try and make some shadows on the wall next to you.

You will probably need a light source.

So you either will need to go where you have a window opposite a wall or if your room is really light, you might need to turn the lights off and get a light source.

Like you could use your phone torch or your parent In front of your hand, onto the wall.

I want you to try and make these different shapes with your hands and see if you can match up the shape of the hand to shape of that shadow puppet that it is making.

So you can see there's a dog, there's a rabbit, there's something that looks a bit like a parrot and then maybe a crocodile, I'm not sure what that, the one that looks like that is.

Have a go at doing those now.

If you don't fancy having a go at making your own shadow puppets, then you can try and match the shape of the hand, the shape of the shadow by just looking at the shapes that match.

Pause the video and a have ago at doing that now please.

Oh, I should say, you don't need to write on your piece of paper because it will be quite hard to draw.

Just have a go at seeing which ones you think would match up.

Just thinking in your head and I'll show you the correct answers in a moment.

Great, I hope you've had a go too, at trying to make your own shadow puppets.

Let's see if you were able to match them up.

So this first one, when you have to use two hands like this, it's actually quite tricky, two hands like this, is how you make the rabbit puppet, that one's really hard.

That took me quite a lot of practise.

The second one matches up to this puppet that looks like a dog.

The next one matches up to the puppet that looks a bit like a parrot, maybe head of a giraffe.

And then the last one is the shadow puppet.

The hand that matches up to the shadow puppet that looks a bit like a crocodile.

So I hope you had a little bit of fun matching those up.

If there were any that you found really tricky, maybe you can practise them later.

Now, we are going make our own shadow puppet theatre.

So using the shadows, specially designed to specific to shaped opaque materials, we can create characters on a screen that's known as the shadow theatre.

So we're going to have to use an opaque material as our screen for our theatre.

And then we're going to use, sorry, we're going to have to use a translucent material.

My mistake, a translucent material for the material of our theatre and then opaque materials for our shadow puppets that are going to go behind.

It's believed that this form of theatre originally started in China or Indonesia, and it's still used to tell stories in many places across the world.

So I'm going to show you how to make a shadow puppet theatre.

Okay, I'm going to show you how to make a shadow puppet theatre.

And you're going to need a few different things for this.

I'll explain what you need now.

You're going to need a pair of scissors.

They do not need to be as big as this.

These are just the only ones that I have.

You need a piece of paper, any kind of paper will do.

However, the thinner it is, the better and plain paper is potentially better as well.

If you have baking paper, which your parents or carers might have in the kitchen, then that would be the best.

Well, I don't have that so I'm just going to use plain paper.

You're also going to need a slightly thicker kind of paper.

So I've got some record cards here that I'm going to use but if you have a piece of cardboard, that would be good as well.

This paper needs to be opaque, it needs to not let like through, okay.

But this is a paper that's going to make the main front theatre should be opaque.

So we should be able to shine light through it, oh, sorry, should be translucent so we should be able to shine light through it.

And you're going to need some cardboard, okay.

Just left over cardboard that you have in your recycling will do, okay.

If you don't have a cardboard box that looks like this, that's okay, you can definitely, this is going to make the outside of our theatre.

You can definitely make it using something else.

I'm sure that you will be able to come up with a creative way.

So if you had tube holders, then you could use that.

So it's making the outside.

If you have plastic in your recycling, then you might be able to use that.

You could even probably scrunch up paper like this, to make the outside of your theatre like that, okay.

So whatever materials you have around, any junk modelling that you have can probably be used to make the outside of your theatre.

I have some cardboard, so I'm going to use some cardboard.

And the first thing I'm going to do is, so I got a big cardboard box here.

I'm just going to get red off the flappy bit stuff.

I don't need any of them, I'm just going to remove them.

Okay, and I'm going to need this bottom flappy bit, this bottom fold on 'cause it's going to help my theatre to stand up.

Okay, so ideally, you want, I'm going to cut these last pieces off.

Ideally, you want kind of a piece of cardboard like this.

So you have a bottom flat and then the flap bit on he surface.

It might actually, I've just done it now.

So it might actually have helped to have the sides on as well, 'cause then it would have stood up, even if that flap wouldn't do, we do with what we've got, okay.

And I'm going to bend it down like this.

Great, okay.

This is the frame of our theatre.

So we're going to need to cut out a hole in the middle.

So before I do that with my scissors, to make sure that I'm being really neat, I'm going to a pen and I'm just going to draw a rectangle, so I know where to cut out.

I could use my ruler to be even neater.

Okay, might, you could either puncture into the middle and cut along with your scissors or you might just need to make a little incision at the top like that and then you can always stick it back together afterwards.

Unfortunately, part of my theatre has already fallen off, but you might have better luck than me.

I think the same is going to happen on the other side.


That wasn't that this bit was meant to happen.

This bit still be here like this and I don't have any sellotape, so I'm going to glue it right on.

Oh yes, I forgot to say at the beginning, you might need to glue as well or sellotape, if you have it.

Okay, not super stable, but when I stick my screen in, that will help hold it together, okay.

You could also leave a strip at the top of your theatre if you wanted to have a frame all the way round.

The next thing we're going to do, is we're going to turn our theatre over like this and we're going to stick our screen onto it there, okay.

I haven't stuck it on yet, so when I lift it up, we'll have my screen that like that.

So I was just checking if my piece of paper fit and then I'm going to get my glue and I'm going to smear it along the edges.

Then, I'm going to stick my screen in and press it down.

There we go.

Okay, so that's my theatre screen.

Now I've done that quite quickly just to show you what it will look like.

You, it's up to you.

You can make a rough theatre like mine, or maybe you fancy doing a bit of a longer creative project.

In which case, you could decorate the outside of your theatre and you could take more care of it and make your theatre look really fantastic, okay.

It's up to you.

Now, this is my theatre, the next thing, and I'm going to put it to the side.

The next thing I need to make is my shadow puppets, okay.

I've purposely chosen a screen here that's translucent.

If I were to shine a torch through the back of my screen, some of the light will go through, so you can see some of the light is going through.

We're in a light room so it's hard to see, but it's definitely going through the paper.

For my shadow puppet, I need a different material.

I need a material that's not going to let the light through.

I'm going to need an opaque material.

So I just pop that to the side.

Either use a kind of thicker piece of paper or card if you have one or any of your cardboard scraps, okay.

You can make any puppet that you want.

I'm going to make a puppet of a man or a person.

And I'm going to draw the outline on my piece of paper and then cut it up with scissors.

So, I'll just show you what that would look like, okay.

Made a bit of a mistake.

It doesn't matter if you make a mistake, because you're not actually going to see the writing.

You're just going to see the outline that you've cut out.

Okay, so there's my person, my outline.

And then I'm going to take my scissors and cut around the person, around the line, okay.

Here's one that I made earlier.

And this is all you need for your puppet.

You can then use your puppet theatre like this and just hold it behind the puppet, well, puppet theatre.

However, if you have, if you have sellotape at home, if you have sellotape at home, then you might want to make a little handle for your puppet.

So you could take a pen and sellotape it to the back of your puppet.

And then you would be able to use your pocket like this and not have to hold it with your fingers.

You can then of course, take your pen back when you're finished with your puppet, or you might even have something like a straw that you could use to make your puppet and stick it on, okay.

And then you got a bit more freedom with moving your puppet in the shadow of your hand doesn't get in the way, but if you don't have those things, then just having the outline of your puppet would work fine too.

And you could even make your shadow puppets using the handshakes that we practised earlier in the lesson.

Okay, so now we have our puppet and we have our shadow puppet theatre.

It's going to be really hard for me to show you exactly how to set this up because it's too light in this room.

And if I turn all the lights off, then you won't be able to see me, okay.

Which is a problem that we've had in other lessons, where we've been looking at light.

So I'm going to show you exactly how you would need to set up and then you can pause the video and have a go for yourself.

Or you might want to watch all the way to the end of the video and then have a long time playing with your shadow puppet theatre later.

Okay, so what you need to do, is you need to have your shadow puppet theatre like this, okay, this is the front of your theatre and this is the back.

At the back of the theatre, is where you'll have your shadow puppet and then you'll have your light source here.

Okay, so shadow puppet will be here and then your light source, you could use the torch and an iPhone or torch if you have one or you could even set up a lamp.

So it will be light source, shadow puppet, theatre.

And then, if you watch from this section, you'll be able to see the shadow of your shadow puppet on the front screen.

Just like the picture of the slide I showed you, okay.

I have two questions I want you to think about when you're having a go with your shadow puppet theatre.

The first is, how can you make the shadow bigger? And the second is, how can you make it smaller? So have a think about that while you're having a go with your shadow puppet theatre.