Lesson video

Hi, everybody.

It's Miss Simkin back again for your next science lesson.

This lesson we are still on our unit of the rock cycle, and we are going to look at a new type of rock today.

Today, we are going to look at metamorphic rocks.

I'm really excited to get started.

So let me share our lesson question with you today.

Today, we are going to answer the question how is metamorphic rock formed? Before we start, we are going to recap some of our knowledge for the last lesson.

So I hope you had a go at doing the pre-lesson quiz and well done if you did, if you've got a few answers incorrect and that's okay, 'cause mistakes are how we learn and we're going to go through some of those answers when we recap our learning from last lesson.

Let's have a look then at what we're going to need for today's lesson.

So for today, you will need a piece of paper, a pencil, a colouring pencil, if you would like to mark your work in a different colour and also a ruler so that when we draw our table in the lesson, you can be really neat and tidy with it.

This is the structure that we are going to follow in our lesson today.

So we're going to start with our star words, then we're going to recap our learning from last time, then we're going to look at why metamorphic rock is called metamorphic rock.

Then we're going to look at how metamorphic rock is made.

And then we're going to look at some different types of metamorphic rock and their properties and their use.

These are our star words for this week.

The star words that are underlined are the key vocabulary that we're going to go through at the beginning of the lesson.

And then by the end of the lesson, we will come back to them, and we'll go through all of the words.

So let's start with heat.

Heat is our first word.

Heat is a type of energy that warms things up.

Pressure is our second key word.

Pressure is a measure of force.

So when we put pressure on something we exert a force on it.

At the moment I'm putting pressure on both of my hands and now I'm putting pressure on my table, okay? Pressure is a type of force.

Our next key word is one from last week, it is igneous rock.

If you can remember how igneous rock is made, say it to your screen now.

Igneous rock is formed when magma or lava cools.

Well done, if you got that right, And then our next key word is properties.

So the properties are the characteristics or traits of something, it's how you might describe them.

So for example, you might describe an object as hard or soft, hard and soft would be its properties.

And then our next two star words are metamorphosis and metamorphic rock, we will describe as we get to them in the lesson.

Ah, that's a picture of how igneous rock is formed, but we're going to look at that now somewhere else on a different slide.

So, let's start with our recap.

Last lesson we learned what rock is.

We learned that rock is made of lots of solid grains that fit together.

We also learned or revised, for some of us, the structure of the earth.

So in the very centre of our earth, we have the inner core, then the outer core, then the mantle, which is the largest layer that's made up of molten rock called magma.

And then we have the crust which is on the outside.

Can you remember the sticky way of remembering that crust is on the outside of the earth? Yes, because we eat breads with crust on it and the crust of bread is on the outside.

So we can remember that crust is on the outside.

We then learned that there are three main types of rock and those are igneous rock, metamorphic rock, and sedimentary rock.

And then we spent all of last lesson looking at how igneous rock is made.

So igneous rock is formed when magma or lava cools and solidifies.

And you might remember from last lesson that I showed you a demonstration of this using an ice cube and chocolate.

We also learned about two types of igneous rock, intrusive, and extrusive igneous rock.

And we'd learned that those two types of rock are different because of where they are made.

So extrusive igneous rock happens when a lava cools outside of the earth surface.

So extrusive is outside.

And then intrusive rock occurs when magma cools inside the earth's surface.

So intrusive inside.

And because of that, because they're formed in different places, they look different, they have different sized crystals.

So extrusive rock has quite small crystals or grains, but it cools very quickly because it's outside and intrusive igneous rock has a big grains or crystals because it calls much more slowly on the inside of the earth.

And this was our sticky way of remembering it.

Intrusive rocks form inside the earth and they have big grains.

Remember that I in big, okay? That's to help us remember those types of rocks.

Great, let's get to our new type of rock, metamorphic rock.

So in this lesson, we're going to learn how metamorphic rock is made, but first, let's see if we can figure out why it's called metamorphic rock.

It's all to do with this word metamorphosis.

Practise saying it with me, metamorphosis, meta.

Great, one more time, metamorphosis.

Good job.

Now, you might have heard this word before in your science learning.

You might have heard it if you've learned about life cycles before, because metamorphosis is often used to describe the process of a caterpillar changing into a butterfly.

But the metamorphosis is a broad term that means when one thing changes into another.

So there's this diagram that helps me remember what metamorphosis mean.

It's when one thing changes into another thing.

So that's why we use it to describe a caterpillar changing into a butterfly 'cause there's one thing changing into another thing.

So why do you think they might be called metamorphic rocks? Hmm.

I wonder what that could have to do with how they're made, if it means one thing changing into another thing.

So rocks can change.

So rocks that undergo a change to form a new type of rock are called metamorphic rocks and that's why we call them that.

So for example, you could start with an igneous rock and that can change into a different type of rock called a metamorphic rock.

An example of when that happens is when basalt changes into a type of metamorphic rock called hornfels, okay? However, we can also create metamorphic rock from sedimentary rock.

So we can start with sedimentary rock, which can change into metamorphic rock.

An example of where that occurs is limestone can change into marble.

So, can you draw a diagram to represent the metamorphosis of metamorphic rock? So can you draw a diagram to show how one type of rock changes into another? I would like you to include labels.

So label is it igneous rock, is it sedimentary rock and also do you use your ruler to keep your diagram really neat? You can pause the video now and complete this task.

Great, once you're finished, let's go on to our next section.

We're now going to think about how metamorphic rock is formed.

So we learned that one type of rock can change into metamorphic rock, but now we need to learn how that happens.

What does that arrow in the middle of mean? Does igneous rock just suddenly turn into metamorphic rock? No, we need certain things for that to happen.

So for example, heat can turn igneous rock into metamorphic rock.

If we apply enough heat to something, it creates a chemical change in the rock and it changes the rock type.

We could also apply pressure to a rock to change it into a different type of rock.

So in order to change igneous rock and sedimentary rock into metamorphic rock, we need to apply either heat or pressure or sometimes both.

Okay, I'm going to show you a demonstration now that might explain that a little bit more clearly.

So this calls for my science box, let me go and grab it.

I'm going to need my lab coat today 'cause this might get a little bit messy.

So let's see what I've got in my science box.

Oh, before we look at this demo, I have another fun fact for you about penguins.

Penguins can actually sneeze salt.

It's true when they dive in sea water, when they're catching that fish, they often inhale lots of saltwater which their bodies don't want.

So they have a gland at the back of their head, behind their eyes that filters out all the salt and then the salt needs to leave their body so they sneeze it's out, which is really cool.

Okay, let's check what we have in our science box.

So today we have two bowls of mush, which is actually exactly what we need for this demo.

So I have a bowl of blue mush and a bowl of red mush.

And what I'm going to do is I'm going to demonstrate how we could apply pressure to something in order to cause a change.

So if I take a big messy dollop of my blue mush and a big messy dollop of my red mush, and I squeeze really hard.

So I'm applying a pressure.

I have changed my blue mush and my red mesh into a purple solid.

So I've applied pressure in order to cause a change which is exactly what happens when pressure is applied to an igneous or sedimentary rock, it changes it into something different.

It changes it into metamorphic rock.

Now, if you would like to have a go at trialling this demo yourself, you can as long as you check with the parent in your house.

If you're going to try, let me give you a few tips before you begin.

First of all, it's quite messy.

So definitely warn your parents this, if you're going to give it a go.

I would make sure that you do it on a surface that you don't mind getting messy, have lots of kitchen roll or tissue to the side and maybe wear something that can protect your clothes.

If you're going to make the mushes then they are made by ripping up lots of little pieces of paper and adding water and then you leave it to soak for a couple of minutes, but the longer you leave it to soak, the more mushy it will be and you might need to get in there and mush it up with your hands as well.

I then added a little bit of food colouring to both, okay? And that's how you set it up.

Interestingly, you could squeege these down, apply lots of pressure and leave it to dry in a flat place.

And if you add a little bit of something sticky, like glue or corn flour you could even make your own paper.

So you could give that a go after the lesson if you have time.

Okay, back to rocks.

So we have learned already that metamorphic rock is formed when you apply heat or pressure to an igneous or sedimentary rock.

I want to show you this diagram now.

Let's have a look at it.

So this shows a section of the earth's crust.

That's what the brown layers are, okay? The earth's solid crust, okay? And that's made of rock.

Now you can see the labels on the bottom.

Let's look at this first, sorry, let's look at this one.

This crust is made of a type of a metamorphic rock.

So this is metamorphic rock forming and we're going to see why the metamorphic rock has formed there.

It shows you that there is some magma rising from a crack in the crust.

Now, when that magma rises that hot magma, it produces heat.

And so heat is applied to that area where the metamorphic rock is starting to form.

This third label also shows us the layers of sedimentary rock.

And there is pressure put on the rock with each layer because it's heavy and it's weighing down.

There are also movements in the earth's crust that applied pressure as well.

So we have pressure coming down from above.

Now, both of those things, the heat from the crack and the pressure from the rocks above and the moving earth, they are forming metamorphic rock in the middle of that crust.

So let's recap our definition.

Metamorphic rock is formed when heat and pressure inside the earth change igneous and sedimentary rock.

Say it with me one more time.

When we say things out loud, it can help us to learn.

Metamorphic rock is formed when heat and pressure inside the earth change igneous and sedimentary rock.

Great, good job.

So now we have some questions to answer.

What are the two things you need to the turn sedimentary and igneous rock into metamorphic rock? And explain how metamorphic rock is formed.

You can use a full sentence for this, and then you could even include a diagram like before to show what you are explaining.

Pause the video and complete these questions now.

Great, let's check our answers when you're ready.

So the two things that you need are heat or pressure.

You can have just one of them, or you could have both of them, but you definitely need either heat or pressure.

And then an answer that you could have written for number two is metamorphic rock is formed when heat and pressure inside the earth change igneous and sedimentary rock.

And well done, if you drew a diagram to support that answer as well.

The next thing we're going to look at is some different examples of metamorphic rock, their properties and their uses.

So before we begin, can you draw this table onto your piece of paper? So make sure you use your ruler so it's nice and neat.

There should be three columns, types of rock, uses, and properties.

And I would say, leave about, if you're using lined paper about four lines for each one, if you're using plain paper, then I would suggest maybe just using the whole page to draw your table so you've got plenty of room.

You can pause the video and complete this now.

Great, now, this table I would like you to be filling it while I'm explaining.

So I'm going to go through some different types of rock now.

And when I explain the type of rock, you need to write the name and the type of rock colour, and then what it's used for in the uses column and its properties, its characteristics in the properties columns.

So we're going to start with marble.

So you can write marble into your types of rock column.

And I'd like you to make notes while I'm explaining.

If you find I'm going too fast and that's okay, just pause the video, write what you need down.

And you can always go back a bit for video if you need to catch up as well.

So this is marble.

There are lots of different types of metamorphic rock, but this is one of the most common.

Marble is used, so this can go in your uses column, in building monuments, buildings and sculptures.

So here are some pictures that show marble that's been cut into tiles to use in buildings for things like countertops or floors and a picture of a statue which is a really common use of marble.

Now marble has some properties that make it really fit for these uses.

So marble is hard like all rocks but compared to other rocks, it's not that hard.

So there's a hardness scale called the Mohs Hardness Scale and it only has a scale of, it's only three on the Mohs Hardness Scale.

You'll see when we talk about other rocks, that three is not that high.

So for a rock marble is not that hard.

That makes it quite easy to curve and to chip away and to make into designs.

And that's why it's so good for making sculptures and ornaments.

Marble also has a really pretty white colour which you can see in the pictures and if you hold up to light, you can see that it's almost translucent.

So something that's translucent lets some light through and so you can see some of the light coming through it and that makes it really attractive and pretty for certain decorative parts of buildings or sculptures again.

So if you need to pause the video and add your notes to the table, if you've already done that, then we're going to move on to the next part which is this, for each type of rock, I would like you to write a sentence.

In the sentence I'd like you to explain why that type of rocks properties make it useful.

So there's a sentence frame at the bottom that you could use but you don't need to.

And it says hmm is a type of rock that is used for.

So here we would write marble is a type of rock that is used for, and then you can use your table if you can't remember what's it useful.

And then we describe it.

It is hmm and hmm, so that's where you put its properties.

It is hard or it is soft and that is why it's a good choice for.

Okay, so pause the video and complete this task now.

Great, once you're finished, let's check an answer that you could have written.

If you don't have exactly the same wording as me, that's okay, as long as you have the same ideas.

So marble is a type of rock that is used for making statues.

It is not as hard as other rocks.

This makes it a good choice for statues because you can carve it.

Well done, if you wrote something similar, you might also have written how it's used in buildings or you might have written about its pretty colour and its translucence.

Pause the video now if you need to edit your answer and add anything to it.

Great, let's look then at our next type of rock.

So our next type of rock is called slate.

So make sure you're checking the spelling carefully when you're writing it into your table.

Slate is a different type of metamorphic rock.

Most of the slate that's mined throughout the world is used to produce roofing tiles.

So here's a picture of what those roofing tiles look like.

So you might have spotted them on the roofs of houses nearby, or even maybe next time you go for a walk outside, you can have a look and use your observation skills and see if you can spot any roof tiles that look like this, that are this kind of colour and see if you think they might be slate.

Slate is really good for making roof tiles for two reasons.

First of all, it can be cut into thin sheets.

So the way that a slate is formed is it's got lots of kind of small, lots of thin layers in it.

And so it means it's quite easy to cut into thin sheets, which is good, you want your roof tiles to be thin.

And also it doesn't absorb much moisture which basically means it's waterproof, which is great because imagine if you had a roof that wasn't waterproof, it wouldn't be good at all.

You'd be very soggy sitting in your living room or your kitchen during this video at the moment.

So if you haven't already, paused the video and put slate's properties and uses into your table.

And then when you're ready, you can have a go at writing your sentence for slate.

The sentence stem is there again if you need it.

So pause the video and complete the task.

Great, once you're ready, we'll mark our answers.

Let's see if you write something similar to me.

Slate as a type of rock that is used for roof tiles.

It is waterproof and can be cut into thin sheets, which is why it's a good choice for roof tiles.

So correct your answer if you need to or add any detail if you need to.

And then when you're ready, we'll look at our last type of metamorphic rock today.

This is a type of metamorphic rock called quartzite.

Quartzite is hard, even for a rock it's hard.

So on the most scale, it is seven.

So if we think about our marble, marble was only three on the scale and this rock is seven, okay, so it's much harder.

This extreme toughness means that when early humans were around on the earth, it was one of their favourite rocks to use as an impact tool.

So an impact tool would be a of tool that you hit things with.

So something like an axe or a hammer, okay? Because it's really tough, it was really good for that.

Nowadays, it's used for construction.

So here's an example of quartzite that's in lots of little pieces and it's been used on railroad tracks.

So next time you're at the train station, have a look down and see if you can spot the little rocks in between the railroad tracks and you'll know that those are quartzite, okay? They are really good for using in railroads because they're so hard and they're so tough and durable.

It means that trains going over them and impacting them over and over again, doesn't break them into smaller pieces.

Great, if you haven't had a chance when I've been speaking, pause the video and write your notes into your table about quartzite.

And then when you're ready, we'll have a look at our sentence for quartzite.

So can you write a sentence that explains why quartzite is good for what it's used for? Pause the video and do that now.

Great, when you're ready we'll take a look at our answers.

So this is what you could have written.

Quartzite is a type of rock that is used for railways and constructions.

It is very hard and durable which is why it is a good choice.

You also could have written an answer about it being used for early tools like axes and hammers.

That was the other example I gave, okay? And that would have been a great answer too.

Amazing, that brings us to the end of our lesson.

So just before you go, let's recap our star words from today.

Our first star word was heat, which is a type of energy that warms things up.

Then we had pressure which is a measure of force.

And then igneous rock was a type of rock we learned about last week.

And then today we learned about metamorphic rock.

Metamorphic rock is rock that is formed when heat or pressure inside the earth changes igneous or sedimentary rock.

We also learned the word metamorphosis, which is when one thing changes into another, which is why metamorphic rocks are named that.

And we looked at the word properties.

So the properties of the characteristics of something, and we looked at the properties of some different types of metamorphic rock.

So we've now learnt two of our types of rock.

So next lesson, we are going to learn about sedimentary rock and then we will have learned about how all three of our rock types are formed.

Well done for all your hard work today.

Thanks again for being so fantastic.

And I will see you back here for the next science lesson.

Have a lovely day.

Bye.