Lesson video

Hi there.

My name is Mr. Tilstone.

I'm a teacher, and one of my favourite things in the whole wide world is maths.

So I feel very lucky and very excited to be working with you today on a lesson all about time.

Sometimes time can seem quite a tricky thing to learn, but don't worry.

If you concentrate and listen really well and you've got a nice positive attitude, you're going to be amazing! So if you're ready, let's begin.

The outcome of today's lesson is I can compare and sequence intervals of time.

So if you can say that at the end of this lesson, you've been successful, and I'm sure you will be.

We've got some keywords today.

My turn, interval.

Your turn.

My turn, shortest.

Your turn.

And finally, my turn, longest.

Your turn.

I suspect you've probably heard shortest and longest before, but you may not know what interval means, so let's explore that today.

The lesson is split into two cycles.

The first will be comparing intervals of time and the second ordering intervals of time.

So if you're ready, let's start by comparing intervals of time.

In this lesson, you're going to meet Alex, Aisha, and Sam.

Have you met them before? They're really helpful.

They're here today to give us a helping hand with our maths.

So have a look at this clock.

This clock is showing the minutes that pass between o'clock and quarter past.

And you might have had some recent experience learning about quarter past.

That hopefully is not new knowledge to you.

This interval of time is the same as quarter of an hour.

So some time has passed, that's called an interval, and that's a quarter of an hour interval.

And that's the same as 15 minutes.

So quarter of an hour and 15 minutes are the same.

Now, this interval of time is also a quarter of an hour, but it's a different quarter of an hour or a different 15 minutes on a different part of the clock.

So this quarter of an hour has gone from quarter past to half past, but it's still 15 minutes.

This is another, a different interval of quarter of an hour or 15 minutes.

And this time you might notice this 15-minute interval is going from half past to quarter to.

Here's another interval of quarter of an hour or 15 minutes.

Can you see this time it's going from quarter to to o'clock? What about this one? This looks a little different.

It's a different interval of a quarter of an hour or 15 minutes.

What do you notice this time? Hmm.

Well, it doesn't start or end at quarter past or quarter to, but it's still 15 minutes.

It's a 15-minute interval somewhere around the clock.

What about this one? This is different again.

This is a different interval of quarter of an hour or 15 minutes.

What's different about this one, do you think? Have a look.

Well, this time it stretches across o'clock, but it's still a 15-minute interval.

So we can say a quarter of an hour is a 15-minute interval of time that can start at any point.

Two 15-minute intervals make a 30-minute interval, or half an hour.

So that's one 15-minute interval and another one together makes 30.

So that's a 30-minute interval and that's half an hour.

Here are some different examples of half hour or 30-minute intervals.

So this one, look, goes from half past to o'clock, which is a bit different to the one before, which went from o'clock to half past.

It's a different one again.

So this 30-minute interval, look, it's going from quarter past to quarter to.

It's 30 minutes again.

And what about this one? This one's going across the hour, across the o'clock.

This one's going from quarter to to quarter past.

It's 30 minutes.

Or what about this one? This one's not going from or to quarter to or quarter past, and it's going over the hour.

This one's in fact going from 5 to to 25 past.

It's a 30-minute interval.

So we can say half an hour is a 30-minute interval of time that can start at any point.

Let's have a look at another interval.

One 15 minutes, two 15 minutes, three 15 minutes.

So a three 15-minute interval makes a 45-minute interval.

15 plus 15 plus 15 equals 45, or three quarters of an hour.

So what you can see there is a three quarter of an hour interval.

This one starts at o'clock.

That's a different 45-minute or three quarters of an hour interval.

This one's starting at quarter past and going to the o'clock, but it's still 45 minutes, or three quarters of an hour.

And what about this one? It's still 45 minutes or it's still three quarters of an hour.

This time it's going from half past to quarter past.

What about this one? That's a different one again.

It's a 45-minute interval.

This one's going from 20 minutes to to 25 minutes past, but it's 45 minutes.

So we can say that any, absolutely any three quarters of an hour is a 45-minute interval of time that can start at any point.

So interval is a period of time, some time has passed.

Let's do another one.

So that's one 15 minutes, two 15 minutes, three 15 minutes, four 15 minutes.

That's four 15-minute intervals together make a 60-minute interval, because 15 plus 15 plus 15 plus 15 equals 60, and a 60-minute interval can also be called an hour.

That is one hour.

Here are some different examples of one hour or 60-minute intervals.

So this one, look, is going from five past to the next five past.

This one is going from 10 past to the next 10 past, or perhaps it's 25 past to the next 25 past, or perhaps it's 20 to to the next 20 to, or perhaps it's five minutes to to the next five minutes to.

But either way, it's a 60-minute or one-hour interval.

So we can say one hour is a 60-minute interval of time that can start at any point.

Do you think you're getting the hang of this interval business? I think you might be.

Hopefully you are.

So let's do a check and let's see.

You're going to match the intervals of time.

So we've got half an hour, one hour, three quarters of an hour, and quarter of an hour.

Can you match them up? So we've got 60 minutes, 15 minutes, 30 minutes, and 45 minutes.

Which one belongs with which? Pause the video and investigate.

How did you get on? Are you ready for some answers? Let's have a look.

So half an hour is the same as 30 minutes.

It's a 30-minute interval.

One hour is a 60-minute interval.

Three quarters of an hour is a 45-minute interval, and quarter of an hour is a 15-minute interval.

Very well done if you got all of those right.

You're ready for the next part of the lesson.

So here's Aisha and Sam again.

They're talking about how long it takes them to do different activities.

Aisha says, "I spent three minutes brushing my teeth last night." Three minutes sounds about right, doesn't it? And, "I spent two hours watching a film last night," says Sam.

So they did two very different things that took different amounts of time.

Aisha says, "Two is less than three, so your activity was shorter." Hmm.

Do you agree with her? Was Sam's activity, watching the film for two hours, shorter than brushing teeth for three minutes? Hmm.

Sam says, "No, Aisha! Hours are much longer than minutes.

Two hours is more than 60 minutes, so your activity was shorter than mine." "Oh, of course," says Aisha.

"It was helpful to think about hours compared to minutes." Now Aisha says, "I spent quarter of an hour reading a book this morning." Oh, good for you, Aisha.

That's what you should do.

That's good.

Sam says, "I spent 20 minutes playing football in my back garden this morning." Good for you too, Sam.

Two great activities there.

So quarter of an hour reading a book, 20 minutes playing football.

Aisha says, "So I could say I spent 15 minutes reading a book.

Now we can compare." So she's getting the idea now, isn't she, of turning them into minutes.

And Sam says, "Yes, 15 minutes is a shorter time interval than 20 minutes.

I spent longer on my activity." So those times sounded very different until we turned them both into minutes.

Aisha is sorting intervals of time into hoops using less than, equal to, and greater than symbols, and you might have some hoops in front of you.

She first compares to half an hour.

So we're starting with half an hour.

She's got a card that says three quarters of an hour.

Where should she put that? Less than, equal to, or greater than? Hmm.

Half an hour is 30 minutes.

Three quarters of an hour is 45 minutes.

So three quarters of an hour is greater than or longer than half an hour.

So it belongs just here with the greater than symbol.

That became easier when we started talking about them in terms of how many minutes they were.

What about this one? So she's still got half an hour.

We know now that's 30 minutes, don't we? Now she's got 15 minutes.

So where can she put that? Well, 15 minutes is less than 30 minutes.

So in that case it's got to go there.

35 minutes.

Now, remember, we said half an hour is 30 minutes and this card's 35 minutes, so where should we put that? It's greater than.

So that belongs here.

30 minutes she's got this time.

So she's comparing half an hour with 30 minutes.

Is that greater than, equal to, less than? What do you think? Half an hour and 30 minutes are the same interval of time.

They're equal, so therefore it goes just there in that sorting hoop.

Let's have a check for understanding.

Let's see how you're getting on.

Which interval of time has been incorrectly sorted when comparing to 45 minutes? So we're looking at 45 minutes this time, and we've got 10 minutes in the first hoop, three quarters of an hour in the middle hoop, and half an hour in the right hoop.

Which one's wrong? Pause the video.

Did you spot which one was incorrect? Did you manage to check that with somebody near you? Let's have a look.

Half an hour is 30 minutes and 30 minutes is less than 45 minutes, but it's in the greater than one at the minute.

So it in fact belongs just here.

Well done if you got that.

It's time for some practise.

So the first task is to work in pairs or groups if you can.

Turn over all of the cards.

You've got some cards in front of you, turn them over so that you can't see what's on them and then choose one randomly as the one that you're going to compare the other cards to.

And then sort the other cards into the correct hoop, greater than, less than, or equal to, just like we saw before.

When you're finished, give them a shuffle and have another go.

See if you can do it maybe a bit quicker this time.

And number two, write to your own intervals of time in the sorting circles on your worksheet.

So we've got quarter of an hour.

So what is less than that, what's equal to that, and what's greater than that? Pause the video, good luck with that, and I'll see you soon for some answers and feedback.

Welcome back.

How did you get on? Let's have a look.

Well, for the first one, there's lots and lots of things that you could have done, but here's one example.

So you might have chosen the card 30 minutes, and that's what you're comparing the other ones to.

And that being the case, in the less than circle you might have put quarter an hour or 20 minutes, in the equal to you might have put half an hour, and in the greater than you might have put three quarters of an hour or one hour.

That's just one example.

And number two, there was all sorts of things you could have written into these hoops, but here's just some examples.

So this is a quarter of an hour.

Well, five minutes is less than quarter of an hour, so we can put that in the red hoop, the less than hoop.

15 minutes is equal to quarter of an hour, so that can go there in the middle one.

And then half an hour is greater than quarter of an hour.

So that's one of many examples of times that can go just there.

Hopefully you got lots of other ones as well.

Well, I think you're ready for cycle two because you are doing amazingly well.

So Aisha and Sam are talking with Alex about how long it takes them to do different activities, just like they were before.

This time Alex is joining in.

So Aisha's saying, "I spent three minutes brushing my teeth last night." We knew that already, didn't we? They're telling Alex now.

And Sam says, "I spent two hours watching a film last night." We knew that already.

They're telling Alex.

So what's Alex done? I wonder, let's have a look.

Alex says, "I spent half an hour doing my homework last night." Oh, well done, Alex.

That's fantastic.

But they're very different times.

The time intervals can be put into order from shortest to longest, but we need to do something first.

It may be helpful to think about how many minutes each activity took.

So we already knew about Aisha's activity.

It took three minutes.

But Sam's, she says, "I spent two hours watching a film last night." Well, we could say one hour is 60 minutes, so two hours is 120 minutes.

It's certainly more than 60 minutes.

And then Alex says, "I spent half an hour doing my homework last night." Now, you might remember, and hopefully you do off by heart what half an hour is in minutes.

Do you know? Half an hour is 30 minutes.

So now we've got three times that are in minutes, 3 minutes, 120 minutes and 30 minutes.

Now it's a bit easier, isn't it, to put them into an order.

Here we go.

So we're starting with Aisha's.

Her activity took three minutes, then Alex's activity took a bit longer, that's 30 minutes, and Sam's activity took even longer, that's 120 minutes, and now they're in order from shortest to longest.

We've put them into order.

Aisha's ordering intervals of time from shortest to longest and she's got these cards: quarter of an hour, 60 minutes, 45 minutes, half an hour.

Now, did you notice that two of them were already in minutes? So I wonder if we could change the other two so that they're in minutes too.

But let's order them from shortest to longest.

And again, you might have some hoops in front of you, so you can do this too.

Aisha says, "Maybe it would help if I changed them all into minutes." I do think that's a good tip.

That's a top tip.

So quarter of an hour is the same as 15 minutes and half an hour is the same as 30 minutes.

So now they're all in minutes, we can say 15 minutes is the shortest interval of time.

So that's where we're putting quarter of an hour or 15 minutes.

Half an hour is next.

It's the same as 30 minutes, which is longer than 15 minutes.

So that's going to go just here.

45 minutes is next.

That was already in minutes and it's longer than 30 minutes.

So we're going 15 minutes, 30 minutes, 45 minutes, and that just leaves 60 minutes.

And that's the longest interval of time and that's the same as one hour.

And I think you knew that already, 60 minutes is one hour.

So there we go.

Now they're in order from shortest to longest, those time intervals.

Let's have a check.

So Sam is ordering intervals of time from shortest to longest and she's done this.

So starting with the shortest, she's gone five minutes, half an hour, quarter of an hour, three hours.

Is she correct? Pause the video.

What do you think? Was she correct? No, she wasn't.

Did you manage to spot the mistake? She was almost correct.

But quarter of an hour is shorter than half an hour.

When we turn those into minutes, half an hour becomes 30 minutes, quarter of an hour becomes 15 minutes.

So 30 goes after 15, not before.

That's the right order.

Five minutes, quarter of an hour, half an hour, three hours.

Time for some more practise.

Use the numbers one to three to order these time intervals from shortest to longest.

So Aisha is saying, "I spent three quarters of an hour reading a book," Sam says, "I spent half an hour painting a picture" and Alex is saying, "I spent 40 minutes playing on a video game." So put a number one next to the shortest, a two next to the one after that, and a number three next to the longest.

And then number two, so you've got all those cards still from the first part of the lesson.

Turn them over, shuffle them so you can't see what's on them, and then choose four cards randomly and sort the intervals from shortest to longest and keep practising this.

Now, if you turn over a couple of cards that are the same, so I'll give you an example, quarter of an hour and 15 minutes, put them in the same hoop.

Good luck with that.

Pause the video and I'll see you soon.

Welcome back.

How did you get on? Do you think you're getting good at these time intervals now, putting them into order and what have you? Let's have a look.

So, number one, use the numbers one to three to order these time intervals from shortest to longest.

The shortest was this one, half an hour, that's 30 minutes.

And then this one, which is already in minutes, that's 40 minutes.

And there's this one, three quarters of an hour, which is 45 minutes.

So that's the right order.

And then there are loads and loads of possibilities for number two, different things that you could have done.

Here's just one example.

So you might have turned over these four cards.

And in order from shortest to longest, that would've gone five minutes, half an hour, 35 minutes, one hour.

That shortest to longest.

Or you might have done this one where two of them were the same.

So five minutes, and then in one hoop 15 minutes and quarter of an hour, and then in the final hoop, three quarters of an hour.

So they're in order too.

We've come to the end of the lesson.

I've had so much fun exploring this concept with you of comparing and sequencing intervals of time.

So, intervals, that word that you might not have known at the start of the lesson, but hopefully you do now, intervals of time can be compared using greater than, equal to, and less than symbols.

They can also be ordered from longest to shortest or shortest to longest, and you've done lots of practise ordering them from shortest to longest.

So here's an example, look.

From shortest to longest, it goes quarter of an hour or 15 minutes, half an hour or 30 minutes, 45 minutes, 60 minutes.

And my top tip to you is convert them into minutes.

Change them into minutes, then they're easy to compare and easy to put into an order.

You've been amazing in this lesson.

I've had so much fun working with you and I really hope I get the chance to work with you again in the future.

But until then, enjoy the rest of your day.

Take care and goodbye.