Lesson video

Hi there, my name is Mr. Tilston.

I'm a teacher.

I teach all of the different subjects, but my favourite one just has to be maths.

So it's my great pleasure and great delight today to be teaching you a lesson all about time.

Time can be quite a tricky concept, there's a lot to know.

There's a lot to remember, there's a lot to think about, but don't worry, I'm here to guide you every step of the way.

Remember, practise makes perfect.

So if you are ready, I'm ready.

Let's begin.

The outcome of today's lesson is, I can convert from days to weeks and months to years.

Our keywords today, my turn, day, your turn, my turn, week, your turn and my turn, month, your turn.

They're very common words.

I guarantee you've heard those words a lot and use those words a lot, but let's have a little reminder about the meanings of those words.

So a day is any 24 hour period.

A week is any seven day time period and a month is one of the 12 parts of the year.

Our lesson today is split into two cycles.

Converting from days to weeks will be cycle one and cycle two will be converting from months to years.

So if you are ready, let's start by converting from days to weeks.

In this lesson, you're going to meet Sophia and John.

Have you met them before? They're here today to give us a helping hand with our maths.

John says, "It is 15 days until my birthday" and Sophia says, "My birthday is in exactly two weeks time." Hmm, what did you notice there? Whose birthday is first? It can be difficult to say because John has given his duration in days and Sophia has given hers in weeks.

It would be helpful if they could either both say the number of days or both, say the number of weeks.

We need to convert.

So a week is any seven day period of time.

I bet you knew that already.

This example shows the weeks going from Sunday to Sunday.

So can you see the letters? So S is for Sunday, M for Monday, T, Tuesday, W, Wednesday, T, Thursday, F, Friday, S, Saturday, S, Sunday, and it goes around again.

So here we go.

Seven days or one week from Sunday to Sunday.

Another seven days or one week from Sunday to Sunday and another seven days or one week from Sunday to Sunday.

So they're weeks.

Now this example shows the weeks going from Wednesday to Wednesday, because don't forget, it can be any seven day period of time, not just on Sundays that it starts.

So this example look goes Wednesday to Wednesday, seven days or one week, Wednesday to Wednesday, seven days or one week and Wednesday to Wednesday, seven days or one week.

So a week is any seven day period of time.

Now this number line shows the day as numbers.

So can you see, it's not saying SMTW, all that anymore.

It's got numbers instead.

So seven days or one week.

So can you see seven days have gone by there and then another seven days or one week will take us to 14 days and another seven days or one week would take us to 21 days.

So a full week is seven days, a number of full weeks will be a multiple of seven days.

So there we go.

We've got a double number line.

Seven days is one week, 14 days is two weeks, 21 days is three weeks.

So let's have a look at that relationship between the days and the weeks.

One week is seven days.

Two weeks, what do you think is coming up now? 14 days, Three weeks, what's next? 21 days.

So you might see here we're just counting in seven for the number of days.

Four weeks, 28 days, five weeks, 35 days, six weeks, 42 days, seven weeks, 49 days, eight weeks, 56 days, nine weeks, 63 days and 10 weeks is 70 days.

So knowing our seven times table or being able to count in sevens was very, very helpful there.

And John sees it too, he says, "This is just like knowing your seven times tables.

I think I could do this without using the number line." Mm, that's confident.

Well, let's have a look.

It's not necessary to use the double number line if you're able to recall your seven times tables and we've got this stem sentence, mm times seven equals mm.

So there are mm days in mm weeks.

In this example, nine weeks are being converted into days.

So we've got nine times seven.

So the nine is nine weeks times seven, the number of days equals 63.

So there are 63 days in nine weeks.

So knowing our seven times tables was very helpful there.

So let's do a check.

Let's see if you can use your seven times tables knowledge.

Mm times seven equals mm, so there are mm days in mm weeks.

Can you convert 12 weeks into days? Pause the video and give that a go.

How did you get up? Well 12 times seven equals 84 and maybe you knew that fact off by heart and that was automatic, very well done if so.

So there are 84 days in 12 weeks.

Well done if you got that.

You might want to practise with some more examples or you might want to carry on.

Four weeks are multiples of seven when expressed as days.

So one week, that's a full week, that's seven days, two full weeks, 14 days, three full weeks, 21 days.

Non-multiples of seven are part weeks and can be expressed as a mix of weeks and days.

So they're multiples of seven, but what if it's not a multiple of seven? So let's have a look at this example, 10.

10 is not a multiple of seven, but look at it on the number line.

I think it shows two different things.

And we've got another stem sentence that's mm days or mm weeks and mm days.

So let's start by looking at the days.

How many days have passed? Look at the number line.

That's 10.

How many weeks and days have passed? So look how many full weeks have gone by there and how many extra days, a one full weeks gone by and then there's three more days to get from seven to 10.

So 10 days is one week and three days.

Let's do another one.

How many days is that? And how many weeks and days is that? Hmm, start with the days.

Look at the number line.

How many days have passed? 16.

How many weeks have passed? How many full weeks and how many extra days can you see there? That's two weeks, two full weeks and two days.

So 16 days is the same as two weeks and two days.

Let's have a check.

Let's see if you can use that double number line.

Express that duration in two ways.

Mm, days of mm, weeks and mm days.

Pause the video.

Let's see, that's 19 days.

You can see that from the number line or two weeks and five days, well done if you got that.

So let's return to the birthday issue then and John says, "It's 15 days to my birthday" and Sophia says, "My birthday is in exactly two weeks time." So whose is first? Well, Sophia could say my birthday is in exactly 14 days time and then we can compare them or we can go back to what she said and change what John says.

So instead of 15 days, let's say how many weeks and days that is.

Do you know? It's two weeks and one day.

So we can compare them that way, but either way we can see that John's birthday is one extra day away, so Sophia's birthday is first.

The number of days can be partitioned into a multiple of seven plus the extra days.

You might have had some recent experience of doing something very similar to this.

So for example, 17 days can be partitioned into 14 days 'cause that's a multiple of seven and three extra days and let's have a look at that, so this is 17 days, that's 14 days and three days.

So we partition that number 17.

The 14 days is two weeks.

So 17 days is two weeks and three days.

Let's practise using that skill, shall we? So what about 19 days? So counting in sevens, then we can go seven, 14, that's as close as we can get without going over.

So that's 14 plus five and how many weeks is 14 days? It's two.

So that's two weeks and five days.

Let's do another one.

30, right.

Counting in sevens, seven, 14, 21, 28.

Can't go any further.

So that's 28 days plus how many extra? Two.

So 28 plus two.

Now then, how many weeks is 28 days? It's four.

So that's four weeks and two days.

Let's do another.

25 days, count in your sevens.

Do it with me.

seven, 14, 21, stop, can't go any further.

So 25 could be partitioned to 21 and four.

How many weeks is 21 days? Three.

So that's three weeks and four days.

Let's do another one.

38, right? Get ready to count with me.

Seven, 14, 21, 28, 35.

So that is 35 plus three.

Now maybe you didn't even need to count that.

Maybe you just knew that the multiple of seven just before 38 is 35, in which case even quicker, but 38 can be partitioned into 35 and three.

How many weeks is 35 days? It is five.

So that makes it five weeks and three days and what about 48 days? Okay, let's try not counting from zero this time.

Let's think about the multiple of seven that's really close to that, hmm.

42 is the one that you get to before that, so that's 42 plus six, which is the same as six weeks and six days, but there is another way to see that and Sophia's seen it.

I saw the last one as 49 take away one or seven weeks, take away one day, but it still gives the answer, six weeks and six days.

I think Sophia's method was slightly quicker.

So well done to her.

Let's have a check.

Use that partitioning strategy to convert 27 days into weeks and days and is there more than one way to work it out? Think Sophia.

Okay, pause the video.

Did you find a way to work that out? Did you find two ways to work it out? Well, let's have a look.

So 27 days, partitioned, so thinking about that multiple of seven that comes before 27, that's 21.

So that's 21 plus six, 21 days is three weeks, so that's three weeks and six days or thinking like Sophia, you might've seen it like this.

28 days take away one day, that's three weeks and six days still, but just a slightly quicker way to get there.

Well done, if you got that.

It's time for some practise.

Fill in the gaps on the double number line, so you can see the tops got weeks, the bottom's got days and you can see some gaps.

Can you fill those in? Use the stem sentence to convert 11 weeks into days.

So think about your times tables knowledge, your seven times table and number three, express the durations in two different ways.

So how many days is it and how many weeks and days is it? And number four, complete the table, using that partitioning way that we just explored.

Now some examples have been done for you and some are completely blank, so you've gotta do them from the start, but I think you can do that.

So pause a video, good luck and I'll see you soon for some answers.

Welcome back.

How did you get on with that? Did you find it okay? Let's have a look.

So the double number line goes like this, one week, seven days, two weeks, 14 days, three weeks, 21 days, four weeks, 28 days, five weeks, 35 days, six weeks, 42 days, seven weeks, 49 days, eight weeks, 56 days, nine weeks, 63 days and 10 weeks, 70 days.

It's just our seven times table, isn't it? And number two, 11 times 7 equals 77, so there are 77 days in 11 weeks.

Number three, we can express them in different ways.

So let's look at A, that is 13 days or one week and six days and B, that is 18 days or two weeks and four days and then number four, so the same thing as the number line, but just without the number line, same kind of strategies though.

So 15 days is 14 plus one, that's two weeks and one day.

20 days is 14 plus six, that's two weeks and six days.

26 days is 21 and five, that's three weeks and five days, 43 days is 42 and one, that's six weeks and one day and 55 is 49 and six and that is seven weeks and six days.

Well done if you got that.

So I think you are ready for the next cycle.

What do you reckon? Let's give it a go.

That's converting months to years.

John's little brother loves cars.

Have you got a little brother? Does he love cars? Do you love cars? John has saved up his pocket money and wants to buy his brother a toy car as a present for his fourth birthday.

Oh, what a great brother John is.

The car has small detachable parts and there is a warning label on the box.

Hmm, you do see these on toys often, don't you? It says, "Not suitable for children under 36 months." Hmm, John is unsure if he will be allowed to buy the car as he does not know his brother's age in months.

So he knows it in years.

He knows he's going to be four, but he doesn't know it in months and that's giving it in months, so he needs to do some conversion.

He needs a way of converting from months to years.

Well there are 12 months in a year, January, February, March, April, may, June, July, August, September, October, November, and December and I reckon you knew that already.

Counting in steps of 12 helps to see how many months there are in different numbers of years.

So one year is 12 months, two years is 24 months and we could count on those little months individually, but trust me there's 24.

3 years is 36 months.

Can you see what's going on here? We're counting in twelves.

These are multiples of 12.

Before we were counting in multiples of seven, this time in multiples of 12.

This a similar strategy.

Four years is 48 months.

What's going to come up next, do you think? Five years equals 60 months and six years equals 72 months.

Can you see a times tables link here? John says, "We don't really measure in months if it's longer than two or three years." So think about how old you are.

You wouldn't tend to say how many months old you are.

You would say how many years, but for little children, particularly for babies and toddlers, we often say it in how many months they are.

So 36 months is three years and that sign said, "Not suitable for children under 36 months," but John's brother will soon be four years old or 48 months, so he can buy the toy car and John says, "This is just like knowing your 12 times tables." He's right, isn't he? So one year is 12 months, one times 12 is 12.

Two years? Two times 12 is 24.

Three years? Three times 12, 36.

Four years? Four times 12, 48.

Five years? Five times 12, 60.

Six years? Six times 12, 72.

And seven years? Seven times 12, 84.

So seven years is 84 months.

We've got a stem sentence.

Mm times 12 equals mm.

So there are mm months in mm years.

Can you say that with me please? Ready? Mm times 12 equals mm.

So there are mm months in mm years.

Now just you, just you say it, off you go.

And that stem sentence can be used to convert months into years, so let's practise it.

How many months are there in eight years? So we're using our 12 times table and we're thinking about eight times 12.

Eight times 12 equals, do you know this one? You might know it off by heart, brilliant.

You might be automatic with it, fantastic.

You might need to use a little strategy to get there, but what's eight times 12? 96.

So there are 96 months in eight years.

Well done if you got that.

So let's have a quick check for understanding shall we? Use the stem sentence to convert 11 years into months? Pause the video.

How did you get on using your 12 times tables? Well, let's have a look.

11 times 12 equals 132.

So there are 132 months in 11 years.

Well then if you've got that.

If the number of months is a multiple of 12, it is an exact number of years.

So 12 months, one year, 24 months, two years, but if it's a non multiple of 12, it's a mix of years and months.

So let's have a look at an example now.

How much time's passed here? The duration can be described in two ways and we can use another stem sentence.

Mm years and mm months or mm months.

Well we can see two years there.

Can you see two full years? And how many extra months? Four.

So that's two years and four months, but how many months altogether? Now we could count 'em all individually, but we don't need to.

We can count in twelves and then count our extra ones.

So that's 12, 24 and then four extra ones makes 28.

So two years and four months equals 28 months.

This was how old John's baby brother was when he started talking.

So have a look at that.

Can you express that in years and months and then also in months? Let's have a look.

How many years? How many full years? Just one, so that's one year and how many extra months as well as that one year? Hmm, I could see 11 there and I didn't need to count 11.

Do you know what I did? I was inspired by Sophia.

I could see 12 take away one, so that made 11 months and one year and 11 months makes 23 months, because 12 plus 11 equals 23 and here we go.

Look, that's that missing month if you want to do it a nice quick, efficient way.

Let's have a quick check for understanding.

This is how old John's baby brother was when all of his teeth had grown.

Can you express it in two ways? So that's mm years and mm months, or mm months.

Pause the video and give that a go.

Let's start by having a look how many full years.

I can see two full years.

Then how many extra months? Seven.

So that's two years and seven months.

What about the months altogether? Well, two years is 24 months.

I didn't need to count in twelves to get there, I remembered that and so that's 24 months plus an extra seven is 31 months.

So two years and seven months is the same as 31 months.

The number of months can be partitioned into a multiple of 12 plus the extra months.

So a bit like we did earlier with the weeks.

For example, 27 months can be partitioned into 24 months, because that's a multiple of 12 and three months, so let's have a look at that.

That 27 months, can you see 24 months and can you see three months? The 24 months is two years, so 27 months is two years and three months.

So we can use that skill, that partitioning skill to partition months into months and years.

So let's have a look.

18 months, let's think about that.

Think about your multiples of 12.

How close can you get to 18? That's 12 months plus an extra six months.

So 18 is 12 plus six.

How many years is 12 months? One, so that's one year and six months.

Let's do another one.

30 months.

Think about your twelves.

12, 24 stop, can't go further.

So that's 24 and six again.

So 24 months.

How many years is that? That's two years and six months.

So two years and six months.

What about 37? Hmm, 12, 24, 36, that's 36 plus one.

36 months, how many years? Three years.

That's three years and one month.

50 months, now I'm not going to start from zero and count in twelves.

I'm going to think what multiple of 12 comes just before 50 and it's 48.

So that's 48 plus two and 48 months, how many years is that? 12, 24, 36, 48, that's four years.

That's four years in two months.

And 47 months, that's 36 months and 11 months, which makes three years and 11 months.

I bet Sophia's got something to say about this one though and here she is.

I saw that last one as 48 takeaway one or four years take away one month and it still gives the answer, three years and 11 months and I think it was a little bit easier.

So Well done Sophia.

Let's have a check.

Use partitioning to convert 35 months into years and months and is there more than one way to work it out? Pause a video and have an explore? Did you find one way? Did you find two ways? Let's have a look.

So 35 months partitioned, well, 12, 24, that's as close as you can get.

So that's 24 months and 11 months.

24 months is two years, so that's two years and 11 months or thinking like Sophia, you might have thought of it as 36 months, take away one month or three years take away one month, which makes two years and 11 months.

Well done if you've got either of those and a special well done if you've got both of those and time for some practise, so complete the table.

So we've got years in the left hand column, months in the right hand column, can you fill in the gaps please? And use that stem sentence to convert seven years into months, so using your 12 times tables there and then number three, complete the table about how long different animals live for and if you get time you could research some other animals to add to the table.

Pause the video, have fun and I will see you soon.

Welcome back.

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

So number one, complete the table, one year is 12 months.

Two years is 24 months, three years is 36 months, 48 months is four years, and then five years, five times 12 is 60, 60 months and using that stem sentence to convert seven years into months, seven times 12 equals 84.

So there are 84 months in seven years and these animals then, mosquitofish that 17 months, that lives for generally, so you can partition that into 12 and five, making one year and five months.

A mouse generally lives for 23 months, so that's 12 plus 11 or one year and 11 months.

I thought of that as 24 takeaway one, two years takeaway one month.

Siamese fighting fish, they live for 32 months, so you can get to 24 months and then an extra eight months.

That's two years and eight months.

A chameleon lives for 50 months on average.

That's the same as 48 plus two or four years and two months and a hamster 39 months, so that's like 36 plus three, which is three years and three months.

We've come to the end of the lesson.

I've had great fun today exploring these conversions with you.

So we've been converting from days to weeks and months to years.

The seven times table can be used to help convert from days to weeks.

Any number of days can be converted into weeks and days using partitioning and the 12 times table can be used to help convert from months to years.

Any number of months can be converted into years and months using partitioning.

Again, very well done on your achievements today, on the progress you've made and the efforts that you've gone to in today's lesson.

Hopefully I'll get the chance to work with you again for a different maths lesson, but in the meantime, enjoy the rest of your day, whatever you've got in store, take care and goodbye.