Lesson video

Hi everybody.

Today we are going to be applying all of our knowledge on length.

And we are going to be applying it to different types of questions.

I'm really looking forward to today's lesson so let's get started.

Put on your hats, fasten those ties, and tell your computer, "now I'm a mathematician." Great.

Let's get started.

For this lesson, you will need the following resources.

A pencil, a piece of paper, and your ruler.

If you haven't got any of those things please pause the video now to go get them.

Great.

Let's get started with our lesson.

What unit of measurement would you use to measure these real life objects? Excuse me.

Millimetres, centimetres, or metres.

The kitchen table.

The height of a house.

A rubber.

Or an eyelash.

Now for the kitchen table, I wouldn't use millimetres 'cause they're too small.

I might use centimetres or I might use metres.

So I'm going to say, centimetres or metres.

For the height of a house I would definitely use metres.

For a rubber I would use centimetres.

And for an eyelash, eyelashes are really really small, I would use my millimetres.

And now it's your turn.

Pause the video and have a think.

What unit of measurement would you use to measure these real life objects? Millimetres, centimetres, or metres? Pause the video.

Great job.

For a toy car, I would measure it in centimetres.

Length of a football pitch would be in metres.

A pillow would be centimetres.

And a grain of rice would be millimetres.

And that is question one.

Let's do question two together.

Here we have a ruler and a calculator.

Three children measured the same calculator.

Coco says that it's six centimetres and seven millimetres.

Josh says the calculator is six centimetres.

And Walid said the calculator is four centimetres and five millimetres.

Who is correct? Who is incorrect? Explain why.

Well having a look at the ruler and carefully reading the measurement scale, I can see that Coco is correct.

And the calculator is six centimetres and seven millimetres.

Unfortunately josh only counted the centimetres.

He didn't add on the millimetres.

And I'm not sure what Walid was up to.

It looks like he's managed to read the ruler completely wrong.

Remember you're only as accurate as your measurement tool.

So you need to be really careful.

So it's your turn.

Here we have an arrow.

Three children measured the same arrow.

Sarah said that it's 12 centimetres and zero millimetres.

Cathy says the calculator is 11 centimetres.

Jack says the calculator is 12 centimetres.

Who is correct? Who is incorrect? Why? Pause the video.

Write down your answer.

Well done.

Having a look closely at the measurement you can see that Sarah and Jack are both correct.

Because the arrow measures 12 centimetres.

Or 12 centimetres and zero millimetres.

Unfortunately Cathy stopped at this edge of the arrow.

She forgot about measuring this bit here.

Great job everyone.

Let's continue on to the third question.

Here we need to match the equivalent measurements.

We have 100 centimetres, six centimetres, 45 centimetres, 300 centimetres, 450 millimetres, one metre, three metres, and 60 millimetres.

Well I know that 100 centimetres is equivalent to one metre.

And because there are 10 millimetres in one centimetre, I know there's going to be 60 millimetres in six centimetres.

And I know that 45 centimetres will have 450 millimetres.

And 300 centimetres are in 3 metres.

And now it's your turn.

Pause the video.

Well done everybody.

10 centimetres is equivalent to 100 millimetres.

900 centimetres is equivalent to nine metres.

35 centimetres is equivalent to 350 millimetres.

And 150 centimetres is equivalent to 1.

5 metres.

Great job, give yourselves one, two, three well done me.

Nice job.

Four friends are building towers.

Jane's tower is 22 centimetres and seven millimetres tall.

David's tower is 22 centimetres tall.

Henry's tower is 215 millimetres tall.

And Laura's tower is 260 millimetres tall.

Order the children's towers in descending order.

So here we have our four towers.

So the four children and the measurements.

But they're not all in the same unit of measurement.

So what you need to do is convert them so they are all centimetres.

So Jane's is 22 centimetres and seven millimetres.

David's is 22.

Henry's becomes 21.

5.

And Laura's becomes 26.

And now you can put them into order.

So Laura's is the tallest.

Followed by Jane's.

Followed by David's.

And followed by Henry's.

So we have used our alligators, which like to eat the greater amount, and we can see that Laura's is the greatest or tallest tower.

So now it's your turn.

Read the question carefully and answer.

Pause the video.

Well done everybody.

So four friends are growing sunflowers.

Lottie's flower is 10 centimetres and three millimetres tall.

Olly's flower is 100 millimetres tall.

Dayna's flower is 110 millimetres tall.

And Annabel's flower is 10 centimetres and four millimetres tall.

Order the children's flowers in descending order.

Dayna's is the largest because it is 11 centimetres, 'cause remember we need to convert them.

Followed by Annabel's which is 10 centimetres and four millimetres.

Followed by Lottie's at 10 centimetres and three millimetres.

And lastly Olly's which was 10 centimetres or 100 millimetres.

Great job.

Well done everyone.

That was lots and lots of practise.

And now it's time to put all of that knowledge to use.

Good luck.

On the next slides you have your independent task.

Please pause the video at each task and complete the questions.

Great job everybody.

So we're now going to go through the answers together.

So please make sure you got a different coloured pencil or the pencil that you're using to do some ticking or fixing.

So fingernail you'd measure in millimetres.

A pencil, you'd measure in centimetres, a rubber you'd measure in centimetres, and the height of a fridge would be in metres.

So for question two, Dexter is correct.

The other two children have not lined up the ruler correctly.

Eva started at one centimetre and five millimetres instead of zero.

And Annie started at the end of the ruler.

So here we're going to be matching the equivalence.

100 centimetres is equivalent to one metre.

Five metres is equivalent to 500 centimetres.

300 centimetres is equivalent to three metres.

And two centimetres is equivalent to 20 millimetres.

And finally for our flower, it should be Dayna's, Annabel's, Lotties, then Olly's.

So Dayna's is the greatest at 11 centimetres followed by Annabel's at 10 centimetres four millimetres.

Followed by Lottie's at 10 centimetres and three millimetres.

And Olly's at 10 centimetres or 100 millimetres.

Well done everybody! Give yourselves a big clap and a one, two, three, well done me.

Great job.

If you'd like to share work today, please ask your parent or carer to share your work on Twitter tagging @OakNational and #LearnWithOak.

I had great fun with you today and I'm looking forward to next lesson.

See you again soon.

Bye.