# Lesson video

In progress...

Hi everyone and welcome back to your Number Sense unit.

Today is one of my favourite lessons.

It's an application lesson.

This means that we're going to put all the things that you know about number sense and we're going to be answering different styles of questions about it! And I'm going to be helping you by going through the questions first before you go off and do them all by yourselves.

So, lets get started.

Put on your hats, tighten your ties, tell the computer, "Now I'm a mathematician!" Super! Let's get started! For this lesson, you are going to need the following equipment.

Please make sure you have them.

Pencil, paper and a ruler.

If you need to pause this video, then please do and go grab those bits.

Otherwise, let's get started! Question one.

Can you find 10 or 100 more or less than the given number? So, as you can see here, we have a number 34.

And as it's going up in tens, it becomes 44.

So the missing number here will be 54.

Going up again, 64, 74, and our final number would be 84.

In the second row, you can see we're going up in hundreds.

So it goes from 404, 504.

Can you whisper at the screen what's going to be next.

Oh that's right! It's going to be 604, 704, and I bet you can't guess the next one.

It is 804, and finishing on 904.

So now, it's your turn! Pause this video while you complete the chart.

Well done! That wasn't too bad.

Was it? So we have 58, 68.

Yup, 78, 88.

Brilliant! 98.

Oh! But what's next? 98 add 10.

108.

Great job, everybody! What about the hundreds? They can be quite tricky.

468, 568.

Oh, 68, Miss Hill? 461, 561, 661, 761, 861, 961.

Great job, everyone! Give yourselves a "One, two, three! Well done, me!" Well done.

Question two: Complete the grid.

Now, this is a tricky one.

So let's have a look at the left hand side.

We're having a look at this side first.

So our starting number is here.

My starting number is 20.

And 10 less than 20 is 10.

Going back to 20.

10 more than 20 is 30.

Great job! Let's go down here.

I haven't got a starting number here.

But, I know that 10 less than my starting number is going to be 23.

So what's 10 more than 23? Have a look.

10 more.

If you want to, use your fingers to add on 10.

10 more than 23 is 33.

And don't forget, I need to do 10 more again.

10 more than 33 is 43.

Absolutely! Down here, there's nothing there.

So we're going look at 10 more.

Okay, so 10 more is 48.

So we need to go back 10.

We need to subtract 10.

48 subtract 10 is equal to 38.

And then I need to subtract 10 again! So 38 subtract 10 is equal to 28.

Well done! We've got that first side covered.

Now we need to look at this side where we're dealing with hundreds.

So our starting number is 314.

100 more.

Oh, sorry! 100 less will be 214.

We're taking 100 away.

So you're going back to your starting number.

314 add 100 is equal to? Well done, it's 414.

Let's go to our next row.

There's nothing there.

Oh, okay.

So let's have a look at 100 less.

So, something goes here.

Minus 100 is equal to 76.

So we need to add 100.

And 100 add 76 is equal to 176.

Well done.

And then we need to fill in this third column.

176 add 100 is equal to 276.

Now, in my final column here, there's nothing.

So I've got to go backwards.

So I have a hundred more here, which is 467.

And I know to get my original starting number, I'm going to have to subtract.

467 subtract 100 is 367.

And then I need to find 100 less, which is going be 267.

That was a lot of math there.

And now, it's your turn! So, pause this video and have a practise of completing the grid.

Great job, everybody.

Let's do it together! So here we have our starting number as 56.

10 less is 46.

10 more than 56 is 66.

Here we don't have a starting number.

So let's have a look at 10 less.

So, 54.

To get to here, we have to add 10, which becomes 64.

And we need to add another 10 for this column.

Which is? 74.

Well done.

Now, in this row, we've got two empty columns.

So, let's go to our third column of 10 more.

Here we have 99.

99 subtract 10 to get to our original number is 89.

And then, we need to find 10 less than 89.

Which is? 79.

Well done.

Now, finally, let's have a look over here.

Our starting number is 532.

So 100 less would be 432.

And 100 more than 532 is 632.

In this row, we don't have our starting number.

So let's have a look at 100 less.

So we know we need to add 100 to get back to our starting number.

And 100 add 55 is equal to 155.

And 100 more will be 255.

Great job.

Let's do this final row together.

So here we have 100 more, which is 524.

And our starting number is empty.

But we know to get our starting number here, we need to subtract 100 from 524.

So, 524 subtract 100 is 424! And, finally, 100 less that 424 is 324.

Goodness me! Give yourselves, "One, two, three! Well done, me!" Let's go on to the next question.

Now, we have got one images of some pencils and some exercise books.

You can see, here I have a pack of 100 pencils, another pack of 100 pencils, a pack 10 pencils, 100 exercise books and another 10 exercise books.

And my question's asking me, "How many pencils do I have?" I can see I have 2 packs of 100.

Now, I know with my hundreds, I can do 100 add 100 is equal to 200.

And I need to add that 10.

So that it becomes 210.

Having a look at our exercise books, we have a pack of 100 and we have a pack of 10.

100 plus 10 becomes? Great job.

It becomes 110.

So now we have a subtraction question.

I give away 10 books to another class.

They've gone to the other class.

How many do I have left? So, I need to do 110, subtract 10.

Which is 100.

And, finally, I'm going to buy some more pencils.

And I've bought 100 more pencils for my class.

How many pencils do I have in total? So I need to do 210, add 100, Which is equal to 310.

That's an awful lot of pencils.

So, now it's your turn! Pause this video before moving on.

Super job, guys! Let's run through the answers together.

How many pencils do I have? Well, I can see there's a pack of 100 and there's two packs of 10.

So, I'm going to add my tens first.

10 add 10 is 20.

And 100 add 20 is 120.

So I have 120 pencils.

How many exercise books? Well, again, I can see a pack of 100 and a pack of 10.

So, I have 110 exercise books.

I'm giving 10 of the books away.

Don't want them anymore.

I'm giving them to another class.

And how many do I have left? Well, 110 take away 10 is equal to 100! And, finally, I'm going to buy some more pencils for my class.

So, 120 add 100 is equal to 220.

Next question.

Using digit cards 0-9, can you make the answers to the questions below? So, we have our digits; note, one, two, three, four, five, six, seven, eight and nine.

Those are all the numbers that I have.

And I need to make up the numbers using these to the answers to the questions below.

So, 10 less than 13 add three.

10 less than 13 add three.

So, first of all, I need to do 13 add three.

If I know that three add three is equal to six, then I know that 13 add three is going be equal to 16.

But, the answer's not 16 because I need to do 10 less than 16.

So, we say, 16 subtract 10 is equal to six! 10 more than 7 times 10.

Now guys, I love my 10 times table and I'm going to whiz through them to get to 7.

One times 10 is 10, two times 10 is 20, three times 10 is 30, four times 10 is 40, five times 10 is 50, six times 10 is 60, seven times 10 is 70! So, I need to do 10 more than 70.

70 add 10 is equal to 80.

100 less than 236.

We've just done some subtraction.

So, 236 subtract 100 is 136.

And, finally, 100 more than 231.

Well, 231 subtract what? Subtract 100 more! This why you need to read the question carefully.

231 add 100 is equal to 331.

So now it's your turn.

Pause the video and have a go.

Brilliant job, everybody.

So, the first question is 10 less than two times five.

One times five is five and two times five is 10.

So, 10 take away 10 is Zero! Now, we need to do 10 more than one times 10.

Well, one times 10 is equal to? You got it! 10! So, I need to do 10 add 10, which is equal to 20.

Here's our next one, a subtraction.

100 less than 436.

So, 436 subtract 100 is 336.

And, finally, 100 more than 311.

311 add 100 is 411.

Well done! These are some number patterns.

I love number patterns.

Let's read it together! Write the equation that comes next.

246 take away 10 is 236.

236 subtract 10 is equal to 226.

Spot's starting to notice a pattern here.

226 subtract 10 is equal to 216.

Have you noticed how the next sum always starts with the answer? So this sum must start with 216.

216 subtract 10.

That's equal to 206! So, now it's your turn.

Write the equation that comes next.

Pause this video, have go.

Super job, guys! It is indeed, 526 subtract 10 is equal to 516.

So now, it's your turn.

Over the next couple of slides, and you have the downloadable resource, you have got your worksheets for your independent task.

Good luck! Remember to pause the video and I can't wait to see you one the other side! Great job, everyone! Now, here I've got the answers displayed for you.

So if you pause this video and get your pencil and do some ticking or some fixing.

Here's slide three, question three.

And question four and five.

Great job with your learning today, guys.

You have been so super.

And I'm so impressed.

Keep it up! So now, if you'd like to share your work, please ask your parent or carer to share your work on Twitter, tagging @OakNational and #LearnwithOak.

And I hope to see again soon.

Take care!.