Hello, scientists.

My name is Mr. Wilshire.

In this lesson, we'll be looking at waterproof materials, the review stage.

Let's jump straight into the lesson.

Our outcome for this lesson is to find out about how famous scientists investigate waterproof materials.

How interesting.

Let's slide in.

Here's a list of keywords that are going to come up during the lesson.

Now I'm gonna say them, and I'd like you to repeat them after me.

The first one is scientist.

Great job.

Next up, material.

Now, waterproof.

Great job.

Try this one.

Properties.

And finally, results.

Excellent job.

Well done.

These keywords are going to come up throughout the lesson.

So don't worry if you're not too sure what some of them mean.

The meaning will become clear as we work through the different slides.

The first part of our waterproof materials lesson is reviewing an investigation.

Now here is Laura and Sam.

And there's also a picture of a scientist investigating some properties of materials.

I can see they're wearing their lab coat there.

And it looks like they've got their hair tied back, and they've got some protective gloves on as well.

Hmm, I wonder what it is that they're doing.

Sam says, "Why do scientists think about and test materials to see if they're waterproof?" Laura says, "Scientists tell us which materials are best for making waterproof objects based on their properties." Hmm, that's right, isn't it? Scientists need to check these things to make sure that things are waterproof, or otherwise, we wouldn't know what items to wear when it's raining.

We'd all get wet, wouldn't we? Now these objects need to be made from waterproof materials.

I wonder if you can guess which objects are about to come up.

Have a little think in your head first.

An umbrella, that needs to be waterproof because if I put up a umbrella, and it rained all over it, and I got wet, it would be a pretty useless umbrella, wouldn't it? A raincoat.

The only reason why you would wear a raincoat is to keep the rain off of you.

It wouldn't be very good if you got soaking wet when you wore it.

And of course, a bath toy.

I've got a rubber duck just like that in my bath as well.

It would be a rather useless rubber duck if it just filled up with water, 'cause then it would sink and it wouldn't float around.

All of those items there need to be waterproof.

I wonder if you can think of any other waterproof objects that you might play with or the things that you know.

Pause the video here.

Have a think.

Restart when you've done that.

Well, I hope that you had a good discussion about different waterproof objects.

I wonder what types of things that you chose.

Maybe you chose a pair of wellie boots.

I know that wellie boots need to be nice and waterproof to keep your feet dry.

Otherwise, they wouldn't be very good for jumping in puddles, would they? Stop and think, true or false, scientists think about why different materials are waterproof and not waterproof.

The answer here is true.

Scientists need to think about these things so they can let us know what to wear when it's raining.

Let's justify our answer here.

Why do you think this? Is it because it is useful to know how to make new waterproof materials for objects like umbrellas and raincoats or is it just because that scientists don't like getting wet? The answer here is a, it's useful to know because we need to know how to make these items. It's not just because scientists don't want to get wet.

Jun and Jacob have been investigating different materials.

They need to find out the best material for making a waterproof hat for Jacob's teddy.

Jun says, "I dripped water onto each material and checked whether any water went into the cup.

Waterproof materials don't let any water through." We can see Jun's experiment there and Jacob and his Teddy.

Hmm, just by looking at that photo, I wonder if you can tell if anything is waterproof.

I can see some water on the top of that cup there.

I wonder how it's worked? Being waterproof is a property of some materials, not all materials.

Some materials will let water drip through them.

Alex and Aisha here are reviewing an investigation.

And Alex says, "When we investigate whether materials are waterproof or not, we create a set of results." And Aisha says, "Results tell us what has happened and what we have found out." I can see there's a table there, and the top says material, number of drops of water in a cup, and waterproof or not waterproof.

The denim fabric has a score of eight and the foil has a score of zero.

Hmm, let's delve into this a bit more.

But first, let's stop and think.

The information we get from doing an investigation is called the results, the returns, or the records? Pause the video and have a think.

Restart when you've done that.

The answer is results.

Results are the information we get from doing an investigation.

So here's Jacob with a slightly more expanded version of the results.

And he says, "What do these results tell us?" Well, these results tell us which materials are waterproof and which are not.

How can you tell which materials are waterproof looking at these results? Have a quick chat with your partner and then restart the video when you've done that.

Let's take a quick look at some of these results.

The material is down the left side and the number of drops in the water cup is down the right.

Denim has a score of 10.

Foil has a score of zero.

Cotton has a score of 12.

Plastic has a score of zero.

Wool has a score of 15.

And hessian has a score of 18.

Hmm, I wonder what that tells us.

Is the highest score here the winner? Let's delve into it a bit more.

Waterproof materials do not let water pass through them.

Lucas says, "The materials that let no water through are waterproof." Sofia says, "The materials that let water through are not waterproof." Ah, so in this case then, trying to find the waterproof materials, the lowest score would be the winner.

So if there are no drops inside the cup, that must mean that the material is very waterproof.

So using all of that knowledge, here is Task A.

Part 1 is to review your results.

Have a little look at your results here from testing materials to see if they are waterproof or you can use Jun's on the next slide.

Have a go answering these questions.

The first one is a, which material let the least water through, b, which material let the most water through, c, which materials are waterproof, and d, which are not waterproof, e, which material is best for making a hat for Jacob's teddy.

You can see Jacob's teddy there.

If you don't have any of your own results, you can have a go looking at Jun's results here.

The material is down the left and the number of drops in the water cup is down the right.

Have a go at that task and restart the video when you've done that.

Best of luck.

Now let's review some results.

These answers are based on Jun's results, but yours might be slightly different.

The first bit there says the plastic and the foil let through the least amount of water.

Then it says the hessian let through the most water.

The plastic and the foil are waterproof materials.

And the hessian, denim, cotton, and wool are not waterproof materials.

The plastic or the foil are best for making a waterproof hat for teddy.

Using these results, we've been able to determine which type of material let through no water.

That means that it's really waterproof.

All the other ones let through a little bit of water, so they wouldn't be that great at keeping things dry, would they? Let's move on to the next part in our lesson.

The next part of our lesson is called material scientists.

Let's jump in.

Now famous scientists in the past have helped us to learn about waterproof materials.

You can see there the ground getting very, very wet from the rain.

When it rains, I wonder what kind of clothes that you would wear.

Take a moment to have a think and restart the video when you've done that.

Great discussion.

Hmm, I wonder what you thought of.

How about a woolly hat and a scarf? Oh, I know, gloves.

Wait, hang on, those don't sound like waterproof materials, do they? And I wonder what kind of things that you came up with.

Maybe you thought about some of these.

You might wear a raincoat and some wellies, or maybe you even thought of an umbrella that you would carry in the rain as well.

Hmm, what do all of these things have in common? Pause the video and have a quick think.

What do they have in common? Restart when you've done that.

So these two pictures are pictures of someone who is trying to keep dry in the rain.

There's a raincoat, and wellies, and umbrella.

And what do they all have in common? Well, they're all made from waterproof materials.

Like we've said before, it wouldn't be very good if the clothes that you're wearing or the umbrella that you had above your head let's all the rain soak through.

Otherwise, you'd be wet all the time.

Here is a picture of a scientist.

His name is Charles Macintosh.

He was born near Glasgow in Scotland in 1766.

He was a scientist who made the very first waterproof material.

Charles Macintosh is there, a very good portrait of him.

It's not a photograph, is it? Because this was from a very long time ago.

This was probably drawn by somebody.

Glasgow is at the very top of the United Kingdom there.

You can see it on the map.

I wonder if that's close by or is very far away from where you are.

Now Charles investigated and he found out that he could melt rubber and brush it onto a woollen fabric.

There you can see a drawing of some melted rubber.

There's a bottom layer of woollen fabric.

And Macintosh's waterproof material was made up of these two things.

He then placed another layer of woollen fabric on top of this.

And when he tested it, he found that water didn't pass through.

He had invented a new waterproof material.

So by combining all of those things, he was able to create the first thing that you could keep dry from.

I wonder how people kept dry in the past, or were they just wet all the time? Today, we still call the waterproof coats, today we still call waterproof coats a Macintosh, or a rain mac, and it's all named after him, the inventor.

You can see a picture of lots of different colourful types of waterproof coats.

I wonder if yours is very colourful as well and if it's comfortable.

Let's stop and think here.

Charles Macintosh invented an umbrella, a waterproof material, or Scotland? Pause the video and have a discussion.

Restart when you've done that.

Charles Macintosh invented a waterproof material.

He didn't invent an umbrella, and he certainly did not invent Scotland.

Scientists today and in the future will help us to learn more about waterproof materials.

How do you think that they can do this? Pause the video and have a quick discussion.

Restart when you've done that.

So how are they going to do that? Well, they need to ask lots of questions and test the different materials.

That way, they can find new ways of making waterproof materials.

You can see someone there with a gloved hand, and they're exploring some materials, and they're using a microscope to observe some materials as well.

How fascinating.

True or false, scientists today help us to learn more about waterproof materials.

The answer here is true.

Can we justify that? Why do we think this? Is it because that they're very clever or is it because they investigate the properties of different materials? The answer is because they investigate.

They look into things, they observe, and investigate the properties of different materials.

Now did you know that materials can be made to be waterproof? I wonder how you think scientists might be able to do this.

Pause the video and have a quick discussion.

Restart when you've done that.

Scientists can make things waterproof, like shoes.

Waterproofing spray can help.

And they can create a waterproof layer.

You can see there an example.

There's a picture of a shoe.

There's a thin waterproof layer and some waterproofing spray that they spray over the top.

That's a very clever invention, isn't it? Materials can be made waterproof by adding an extra waterproof covering or coating using that spray can.

So stop and think.

How can materials be made waterproof? Is it by pouring water on them, measuring how much water passes through them, or adding an extra waterproof layer or covering? The answer here is c, by adding an extra waterproof layer or covering.

So here is the last task of your lesson.

Try and create your own waterproof material.

So start with a material that is not waterproof, like cotton.

Then add an extra layer using glue, or wax crayon, or some of your own ideas to make it waterproof.

Observe if any drops of water pass through your new material.

So you're going to need some squares of cotton, some PVA glue and a spreader, some wax crayons, and, hmm, anything else? You decide.

Pause the video.

Restart when you've done that.

Good luck.

Hopefully you've had a good chance to explore your own waterproof material.

You've created your material and then you've tested it out to see if any water can pass through it.

Your results might look a little something like this.

When we tried with cotton, we found that lots of water was able to pass through it.

When we found that cotton was covered with a wax crayon, we found that no water could pass through it.

When it was covered with PVA glue, a little bit passed through it.

And the tracing paper, nothing passed through it.

So I can have a think here about my results, and, ah, the cotton covered with wax crayon was the most waterproof, along with the tracing paper.

The PVA glue was good, but it let a small amount of water through.

So the two best things that I can use is the wax crayon and the tracing paper.

Let's summarise our lesson.

The results of an investigation can tell us which materials are waterproof and not waterproof.

Scientists think how waterproof materials can help us.

Scientists in the past have helped us to learn more about waterproof materials.

Materials can be made waterproof by adding an extra waterproof covering or coating.

Here you can see a child with some waterproof materials as well, like an umbrella and some wellie boots.

Using your investigation results, I'm sure you'd be able to think of some different ways that you could invent something to be waterproof.

I wonder if you'll be the next waterproof inventor of the future.

Whatever you get designing, and inventing, and thinking about, or exploring, best of luck.

My name has been Mr. Wilshire.

Thank you very much for listening.