Lesson video

Hello there, my name is Mr. Tilstone.

I'm really excited to be working with you today on a negative numbers lesson.

So if you are ready, let's begin.

The outcome of today's lesson is as follows, I can interpret numbers greater than and less than zero in different contexts.

So keywords, my turn, your turn, ready? So my turn, temperature, your turn, my turn positive, your turn, my turn, negative, your turn.

And let's look at the meanings of those words.

Some of those might be familiar to you already.

So temperature, quite a common word is how hot or cold something is, and generally in the UK it's measured using the Celsius scale.

Numbers greater than zero are positive, and numbers less than zero are negative.

Our lesson today is split into two cycles.

The first being temperatures can be above, equal to or below zero, and the second cycle will be interpret positive and negative numbers.

But we'll start with temperatures can be above, equal to or below zero.

So if you're ready, we'll start.

Temperatures in different parts of the United Kingdom can be different.

So consider this.

Is the temperature above zero, equal to zero or below zero? Let's have a look at some different examples.

So here's a thermometer.

See if you can see where zero is on the thermometer.

Then decide if it's above, equal to or below.

So in London the temperature is above zero, therefore it is positive.

It's a very important concept.

It's above zero.

So it's positive.

In Cardiff, a different part of the UK, it is colder than it is in London.

The temperature is exactly zero.

So if you have a look at that thermometer, look where the red line goes to, it goes to zero exactly.

Zero is neither positive nor negative.

So it's a special number.

It's not a positive number, it's not a negative number, it's neither, and it's the only number that's neither positive nor negative.

In Glasgow in Scotland it is colder than it is in Cardiff.

A really cold day here on this thermometer, the temperature is below zero, it is negative and you can see that.

So if you find the zero, you can see that's appearing below the zero.

So it's a negative temperature.

This temperature is above zero.

It's hotter than zero degrees Celsius.

For temperatures above zero or greater than zero the further the temperature is from zero, the hotter it is.

So let's have a look at some examples of that.

So we've got our first thermometer, then our second thermometer, the middle one, you can see the number is higher.

It's further above zero, so it's hotter.

And the third thermometer is even further above zero.

So it's hotter still.

So those three temperatures are getting hotter as they go along.

Now by the same token, for temperatures below zero or less than zero, the further the temperature is from zero, the colder it is.

So let's start with our first thermometer on the left, and then the second one is further away from zero.

So it's getting colder.

And the third one is further away from zero still.

So it's getting colder still.

Let's do a little check for understanding.

Let's see if you've got the learning so far.

So true or false, temperature A is colder than temperature B, is that true or false? And you're going to justify your answer.

So here's your choices.

So maybe you think A is showing a lower number, so it must be colder, or maybe you think both are below zero, but B is further away from zero.

So it must be colder.

Or you might have your own justification.

Pause a video and have a go.

Let's have a look.

That's actually false.

Both are below zero as you can see, but B is further away from zero, so therefore it must be colder.

Do you think you might be ready for some independent practise? Let's find out.

So task A, number one, follow the instructions for each thermometer.

So you've got some thermometers, some picture thermometers.

So for A, you're going to give a temperature above zero for B, a temperature greater than zero, for C, a temperature which is positive, for D, a temperature below zero, for E, a temperature less than zero.

And for F, a temperature which is negative.

And after you've done that, see if you notice something about A, B, and C, have they got something in common? And what about D, E and F? Have they got something in common? So here's your thermometers that you're going to be working with.

And for task two, you're going to underline the correct options and fill in the gaps.

So the temperature in London is that positive, negative, or neither positive nor negative.

So underline the correct one, please.

Is it greater than zero, less than zero or equal to zero in London? And finally it is degrees above or below zero.

So we want a number please.

And then we want you to underline the correct option.

And then we want you to write the same sentences in that same way, that same structure about the Cardiff.

And then finally do the same thing about Glasgow.

Good luck with that task.

Pause the video and I'll see you soon for some feedback.

So for number one then you can put anything that's equal to or above the bar that we're gonna see in a second for B, anything equal to above the bar shown once again.

And then the same for C.

For D, E, and F, anything equal to or below the bar shown.

And what you'll notice about those thermometers A, B, and C is that they're all different ways of saying the same thing.

And the same with D, E, and F.

Different ways of saying the same thing.

So above, greater than and positive all mean the same thing.

And below, less than and negative also mean the same thing.

So let's have a look at the bars.

Here we go.

So for A, B, and C, anything equal to or above that.

And for D, e, and F, anything equal to or below that.

Then for number three, the temperature in London is positive, it's greater than zero and it's actually 12 degrees Celsius above zero.

And you can have any small variations to 12 as well.

You might say 11 or 13, but that kind of number.

For Cardiff, the temperature in Cardiff is neither positive nor negative.

It's equal to zero, it's zero degrees Celsius.

For number three, the temperature in Glasgow is negative, it's less than zero, it's eight degrees Celsius below zero.

And again, you can have some small variations to eight, maybe seven, maybe nine, something like that.

Okay, cycle two then.

So interpret positive and negative numbers.

Are we ready? Look at that house.

Have a little bit of time to look at that house and see what you notice.

Maybe that house reminds you of yours.

Maybe there's something very different about that house compared to yours.

I know certainly there's something very different about that house compared to mine.

A feature that it's got that mine hasn't got.

Okay, let's have a look.

Well, it has floors above the ground.

It's got a floor on the ground as all houses do.

This time and my house hasn't got this.

I'm not sure about yours.

It's got a floor below the ground.

I did use to live in a house that did have a sort of basement before, but my current house doesn't.

So if the floors were to be given numbers, which one would be zero? What would be a sensible choice for that? Hmm? This one, we could call the ground floor zero.

This is more commonly known as the ground floor, but we could attribute the number zero to it.

So if that's zero, what number is this going to be? What is this floor? We could call that the first floor.

And it often is called that as well.

Okay, what about this floor there? That's zero and that's the first floor.

What are we calling this? We could say first basement.

That's a different way of expressing that.

So we've got first floor and first basement.

With houses, it is possible to have floors above the ground.

So above zero and below the ground, below zero.

In the same way as temperatures can be thought of as positive and negative.

So two, can the floors of a house, have a look at that.

Which ones do you think are the positive floors and which ones are negative? Let's have a look.

Well that top floor is positive.

The one just beneath it, still positive.

And then the one beneath zero is negative.

So this house has got two positive floors and one negative floor, one below zero.

And remember, zero is neither positive nor negative.

It's a special case.

We could also use different language as we have before.

We could say that this floor is greater than zero.

So if that one's greater than zero, what about the basement? What could we say about that do you think? We could say it's less than zero.

Let's change the context.

So we've got, let's have a look what we can see on this picture.

We've got a sea context and we've got a land context.

We've got some animals on the land, some animals in the sea.

Now the dotted line represents sea level.

How else might we label it? Think about what we did with the house.

Is there maybe a number we could use to label that sea level? We could call it zero, just like before.

Everything above sea level so that's everything above zero has a positive value, just like it did with the house.

The floors above zero were positive floors.

So in this case, everything above zero, above the sea level has got a positive value.

Then everything below sea level, that is below zero has a negative value.

And remember, zero is neither positive nor negative.

Okay, so here we are, we've got our sea level, that's zero.

We could use different language.

We could say that everything above zero is also greater than zero as we have before.

And everything below zero we could say is less than zero.

So there is different language that we can use to mean the same thing.

Let's do a check for understanding.

We've got a different picture here.

So here, look we've got, we've got sea again just like before.

And we can see a sea level as well.

We've got a lighthouse.

So what language might be used to describe each part of this image? What could we say about A? And can you think of more than one way to describe it as well? What could we say about B? Could we maybe use A in number to describe B? And what about C? Pause the video, talk to your partner and we'll have some feedback shortly.

Let's have a look.

Lots of possible answers here.

We've seen lots of different ways to express the same thing in this lesson.

So we could say.

So this A section is above sea level, it's positive, it's greater than zero and it's above zero.

So well-done to you if you used any of those responses.

And a big well-done if you used more than one, especially well-done if you used all of them.

B, we could say that is sea level.

We could also attach a number to it and that number is zero.

And then C, we could say it's below sea level, we could say it's negative.

We could say it is less than zero.

Over to you for some practise now.

So for task number one, you're going to describe and label that image in as many ways as you can.

Think about all the different ways that we've just seen.

For task two, you're going to describe and label the floors of this hotel in as many ways as you can.

This is a new image, you've not seen this one, but how could you label that hotel? Now let me give you a little clue.

You've seen a house that's got floors above and below zero.

So what about this one? Label that in as many ways as you can.

And finally for number three, this is where you've gotta get a bit creative, draw and label your own image, which shows a zero level, a positive level and a negative level.

Now you can do anything that you think of that would fit those descriptions, but if you're a bit stuck, here's some possibilities.

You could draw a different water context.

So we've seen one with a lighthouse on, we've seen one with a hillside on.

Is there any different ways, different places that you see water, some different examples of water that would do, or about a different building context with above-ground and below-ground section.

So we've seen a house so far and we've seen a hotel so far.

Can you think of a different one? I can think of a shopping centre that's got above-ground and below-ground parts and a car park as well.

Can you think of a different one? If not, you could use those or better still your own completely original idea.

So pause the video, have a go at that task.

Best of luck and I'm looking forward to seeing what you've come up with.

How did you get on? Okay, number one then, label it in as many ways as you possibly can.

Lots of different responses here.

So well-done, if you've got one of these.

And a big well-done if you've got more than one.

So the here we've got the above sea level part.

We could also say that's positive or greater than zero.

And then we've got a zero level, you might call it sea level as well.

And then below that we've got less than zero, below sea level and negative.

Those are all different ways of describing the same thing.

Number two, lots of different responses to this.

You might not have exactly this language, but this is one possibility.

So we've got the zero part is the ground floor.

So both of those are acceptable.

And then above that we've got first floor, second floor, third floor, fourth floor, fifth floor.

And they're all positive.

So you might have used that word.

And then below that we've got first basement, second basement, third basement.

And we could also say they are negative.

So well-done if you've got any of those responses.

So draw and label your own image, which shows a zero level, a positive level, and a negative level.

Well this is one possibility, I was thinking about car parks.

I've been in a car park quite recently where I had to park under the ground, had to go down a ramp to park.

So that's what made me think of that.

So here look, we've got a ground level, which we could also call zero, which you can park on.

You can park on the ground level and then we've got a floor above that.

So you'd have to go up a ramp.

We could say that's the first floor above ground level.

And then below that you'd go down a ramp from the first, from the ground level.

And we could call it the first floor below ground level.

And the one below that we could call the second floor below ground level, you might have had a completely different context and well-done if you came up with something very original for that.

We have come to the end of the lesson.

So our lesson today has been interpret numbers greater than and less than zero in a range of contexts.

And we've seen all sorts of different contexts from sea levels to car parks, to hotels, houses, all sorts.

So there are a wide range of contexts in real life, which show values greater than and less than zero, including thermometers.

That's a really common way to see values above and below zero.

We've seen it with hotels, with floors below the ground.

These can also be thought of as positive and negative value.

So our important vocabulary today are keywords, positive and negative.

Well-done today.

You've been amazing.

I've really enjoyed talking about negative and positive context with you, and I really hope that we can work together again soon.

Until then, take care and goodbye.