Lesson video

Hi everyone, it's Mister Whitehead here, ready for a maths lesson.

I've been thinking about maths, and what it is that's I like about it.

And I've reached the conclusion that when I was at school, I could do the maths, I could follow some rules, perform some tricks, but I didn't really understand the maths and what was happening while I was working through those rules and performing those tricks.

Since becoming a teacher, I've learned how to teach maths to children, so that they can do the maths and really, and truly understand the maths.

That's what I like about it now, being a teacher who knows how to teach maths to children so that they can understand and make connections and really see the maths that they're working with.

I wonder what it is about maths that you like.

Well, I think I'm ready to get started.

I'm in a quiet space and I am distraction free, Can you say the same? If you can't, take a moment by pressing pause to find yourself that space, that is away from distractions so that you can give this lesson, your full attention for around 20 minutes.

Press play again, when you're ready to start.

In this lesson, we will be converting units of measurement.

We're going to start off with a quick activity, for you to practise converting between centimetres and millimetres.

Then we are going to spend some time recapping on connections between kilometres and metres, kilogrammes and grammes, litres and millilitres.

After that, we'll be ready to work on ordering measurements, which will set you up for your independent task to end the session.

The things that you're going to need, a pen or pencil, a ruler, and some paper or a book from school to work into.

Press pause if you need to go and get those things, otherwise, let's get started.

Here we go.

Convert between centimetres and millimetres.

I would like you to look at the value, the measurements I've given you, then look at what you need to convert it into.

So for example, the first one currently is in centimetres and millimetres, I'd like to keep, sorry, I'd like you to convert it into centimetres.

Remember, when we convert from millimetres to centimetres, we're converting from a smaller unit to a larger unit We need to divide by 10, make the number of millimetres 10 times smaller, and then you will have your value in centimetres.

If you're working the other way from centimetres to millimetres, you are moving from a larger unit to a smaller unit.

You need multiply by 10, so that your number increases in size 10 times.

Press pause, have a go at finding the missing values, then come back and we'll check.

Shall we take a look? First one, actually before I reveal, hold up your paper, Let me have a look and see how you got on.

Fantastic.

Shall we check it now? First one, should have seven centimetres, one millimetres how many centimetres? 7.

1.

Next, converting to millimetres multiply by 10, what will your number be? 68.

You've now got 68 millimetres.

Next, 50, no I got 50.

What did you get? Millimetres descend metres.

Millimetres is a smaller unit, I need to divide by 10, to convert it into the larger unit of centimetres, so what you got, is correct.

Half a centimetre, five tenths of a centimetre, 0.

5.

Thanks.

Next.

Good.

And the last one, again multiply by 10, 43 millimetres.

Really good start to the session, everyone.

A quick recap.

Units of measurement, we can measure capacity, length, height, distance, and mass.

And when we do that, we use different units of measurement.

So for example, grammes and kilogrammes, we use to measure mass.

When we're measuring mass, we can use these common benchmarks, to help us estimate first.

So for example, a paperclip or as I've got here, a safety pin, is one gramme.

Whereas this bag of sugar when it was full, and I think it's about a hundred grammes less now this bag was one kilogramme.

So I can feel one gramme, one kilogramme.

Maybe if you get a chance later, find yourself a paperclip or a safety pin, maybe ask a parent or carer to find one for you and a bag of sugar, that's one kilogramme, and just feel the difference.

One gramme, 1000 grammes.

Those common benchmarks help us to estimate.

Millilitres and litres, we use those units to measure capacity and again, it's helpful to have common conversion, sorry not common conversions, common benchmarks.

For example, this carton when filled up would hold 1000 millilitres of liquid, one litre.

Whereas this teaspoon, if filled, would hold around five millilitres.

So if I'm estimating the capacity of a cup, I can think about the five millilitres, the thousand millilitres, the one litre, and I can estimate the capacity of the cup based on what I know about these two, common benchmarks to keep in our minds.

The last type of measurement, we could use metres and kilometres.

And of course there are other units that we can use, for this, for mass and for capacity, but we're just looking at a few today.

Metres and kilometres, we use to measure distances, lengths, heights and a common benchmark to keep in mind, is a metre stick.

I made this a millennium bar to fit it in, I made this metre stick, by measuring out paper with a 30 centimetre ruler, 30, 60, 90 plus 10.

This is the length of the metre.

And when I'm estimating the length of an object, I can keep that benchmark in my mind to help me decide, is it going to be more or less? And how much more or less? Let's have a look at some units of measurement and remind ourselves of the relationship between them.

Grammes and kilogrammes, millilitres and litres, you read these two, and these two.

Good, there's a connection between them of a thousand.

And that connection comes from or can be seen in the prefix of kilo and milli.

Kilo means 1000 times and milli means one thousandths of.

So when I think about millilitres, one millilitre is a thousandth of a litre.

One millimetre is a thousandth of a metre.

Under the grammes and metres, are missing the milli from the start, when we compare them to kilogrammes and kilometres, we've got the same relationship.

One metre is? You say it.

One metre is, one thousandths of a kilometre.

How about grammes? One gramme is, one thousandths of a kilogramme.

What we think of the kilogrammes a thousand times, one kilogramme is a thousand times the size of, one gramme.

One kilometre is a thousand times the size of, a metre.

And again, litres and metres compared to millilitres and millimetres, the kilo isn't there, but the relationship is the same.

One litre is a thousand times the size of, one millilitre.

And for metres? You say it.

One metre is, a thousand times the size of, one millimetre.

Let's have a look at that relationship, between grammes and kilogrammes first.

Press pause, fill in the missing values, come back when you're ready to check.

Shall we look? Go on then.

If a thousand grammes is one kilogramme, if one gramme is a thousandth of one kilogramme, what's missing? Tell me the first one, good, three kilogrammes.

Next.

Super and 1.

5, one and a half kilogrammes.

We can think about the fractions here, 1,500 thousandths, 4,000 thousandths and 3000 thousandths.

Working the other way, from kilogrammes to grammes.

Two kilogrammes is, 2000 grammes.

Eight kilogrammes is, 8,000 grammes and the final one, 1,250 grammes.

The fractions, 1,250 thousandths, 8,000 thousandths, and you say the next one, 2000 thousandths well done.

Let's look at millilitres and litres now.

Press pause, and fill in the missing values.

Shall we check? Wow so these values in millilitres are all less than 1000, so they're all less than one litre.

I think we'll have some decimals, some parts of a litre in our missing body boxes.

Tell me the first.

Good, seven tenths, 70 hundredths, 700 thousandths of a litre, next.

Good, and the last one, 0.

15, 15 hundredths, 150 thousandths, which fraction matches 0.

3? You could say three tenths, you could say 30 hundredths or 300 thousandths.

And the last one.

Good.

Work the other way, press pause work out the missing values, then come back.

Ready? Tell me the first.

Next.

And the last, well done.

As fractions of a thousandths, 1,700 thousandths, so fractions of one litre.

1,700 thousandths of a litre.

So it's more than one litre next.

Good.

And the last one, 6,000 thousandths, we've got 6,000 thousandths, six litres.

Metres and kilometres.

Pause and fill in the missing values.

Let's take a look.

First, it's less than a kilometre, isn't it? Nine tenths of a kilometre, 900 thousandths of a kilometre.

Next.

Good, 0.

06, six hundredths, 60 thousandths of a kilometre.

And last.

Good, 11 thousandths of a kilometre.

Let's have a look at it from kilometres to metres, pause and fill in the gaps, come back and we'll check.

Shall we have a look? First one, 60 thousandths, 600 metres.

Next.

9 hundredths, 90 thousandths, 90 metres, and last 6,000 metres, as fractions, 6,000 thousandths, six kilometres, 90 thousandths, 600 thousandths.

I think we're ready, to use our learning with some ordering.

I have some values in grammes and kilogrammes, that I'd like you to fill in, inside the rectangles.

Notice the symbol between each rectangle, what symbol is that? Less than, something is less than, something is less than, something is less than something.

I'd like you to pause and have a go at filling in those missing boxes, then come back and we'll check.

Let's take a look.

I've got a helpful hint for you, and I wonder if any of you use this anyway, convert the measurements so the units are all the same.

So right now I've got grammes and kilogrammes I could convert so I'm working with all grammes or all kilogrammes.

And we know how to think about that we've just been practising it.

So, if I wanted them all in grammes, half a kilogramme, half of 1000, half of one, 0.

5 kilogrammes, 500 grammes.

Next.

Four tenths of a kilogramme, 40 hundredths of a kilogramme, 400 thousandths of a kilogramme, 400 grammes.

And double 150 grammes, 300 grammes, now look.

I've got four amounts in grammes that I can order and place into the boxes.

So first, the smallest value, 100 grammes next, so next would be 300 grammes.

And let me put the original version of 300 grammes into the boxes, double 150 grammes.

What's next? And last, say it as it was, half of one kilogramme is the largest, 500 grammes.

Okay.

Here's another one.

Pause and have a go the helpful hints are there, convert the measurements so the units are all the same, then order them smallest to largest, pause.

Let's take a look, shall we? How did you convert, into grammes? So two kilogrammes in grammes, double 800 grammes, do we need to convert that? Maybe but we can work it out, what is it? Good, next.

And the last one is already in grammes.

So, which is the smallest? And which is the largest? Good.

Placing the original versions into the boxes next we would need, and then finally the largest that you mentioned, two kilogrammes, next.

Press pause, order from smallest to largest, come back and we'll check.

Use the hint.

Let's have a look.

0.

25 litres in millilitres what is that? 250 millilitres.

Do we need to convert half a 400 millilitres? No, but calculate it.

What is half? 200 millilitres.

One third of 900 millilitres? Split 900 into three equal parts, 300 millilitres.

And the final one, half a litre, a litre is a thousand millilitres, half a litre is? Good, now can you order them? Which is the smallest? And the largest? Okay let's place them, tell me the original versions to put into the boxes, the smallest, next.

Then.

And finally.

Good work.

I think you're ready for your independent task, where you're going to be ordering, five lists of measurements from smallest to largest.

Use the helpful hint, confirm the measurements so that units are all the same.

Then order them smallest to largest.

Press pause, go and complete the activity, then come back and we'll look at the solutions.

Shall we take a look? Helpful hint, convert the measurements so the units are all the same.

Hold up your paper, show me how you got on and give your paper a gentle wave, if you used the helpful hint.

I'm really, really pleased that you did I hope it helped.

Shall we look then? Number one, converting so that those three are all grammes.

We should have 200, 500, 350, then ordered, now I've ordered the converted values, but it would be important to order as well, the original values.

So, this is correct.

And 0.

2, 350, half a kilogramme also correct with those units as well of course, 0.

2 kilogrammes, then 350 grammes, then half of one kilogramme.

Second one, converted so that we're working with millilitres and then the order in millilitres, smallest to largest.

And again the original values ordered, first one 1,500 millilitres, then 1.

6 litres, then two litres.

Last one, on this first section converted into metres.

Although half of one kilometre didn't need to be converted, but we just calculated half of 1000.

And in order, fourth, converted into millilitres, some of you may have been converting into litres, and ordering that way, we'll have the same solutions, and ordered.

So I've ordered the converted values, but of course I can think about that being half a litre, 750 millilitres, 0.

8 litres and then 900 millilitres.

The final one, converting into grammes halving 3000 grammes, doubling 0.

9 kilogrammes, converting into grammes and ordered like that.

So how did you get on? Was the helpful hint useful? Were you able to, order the values once they all millilitres or all grammes? Good work.

Let's finish up with a short activity, which is the shortest? And which is the longest? The helpful hint is there.

Press pause, have a go, then come back and we'll check.

How did you get on? Which unit did you convert these four measurements into? I chose metres, I converted into centimetres by dividing by 10, then into metres by dividing by a hundred.

Three tenths of a metre, 30 hundredths of metre, yeah.

0.

02 kilometres converting into metres, I have multiplied by 1,000, 20 metres.

Now I've got three values that's are all metres oh no, there's one that's still centimetres, 1.

8 metres divided by 100.

Now have I got three values? Yeah, that's three, four values that are metres.

Now, I can look and say, which I think is shortest and which is longest.

So, which did you say was shortest? And longest? Good work.

Made easier, if you use the helpful hint than if you were just looking at each of those values as they were.

If you would like to share any of your learning from this lesson, with Oak National, please ask your parents or carer, to share your work on Twitter, tagging @OakNational and #LearnwithOak.

Thank you everyone for joining me in that maths lesson.

I said at the start, that I really enjoy maths and teaching maths to children.

I hope that you've had just as much fun as I have.

I'm really proud of everything that you've done during this session, and I look forward to seeing some things on Twitter, if your parents and carers are able to help you with that at a later point.

With whatever you have lined up for the day, I hope you enjoy and do it with a big smile on your face.

Thank you for joining me and see you again soon for some more maths.

Bye.