Lesson video

And welcome to today's session.

We're going to be continuing our unit on exploring calculation strategies and today's session, we're going to be solving word problems. For this lesson, you will need a pencil and some paper.

Please pause the video to go and get these things now if you haven't got them already.

Okay, I thought I'd start today's session with a little hello from my dog Arlo.

He has actually gone to go for a groom this week, so he's come back looking very fresh and very, very handsome, although he's not too sure about his new look.

But there's a little picture so you can see how he looks after his nice fresh groom.

Right then, let's get started.

So today's agenda.

We're going to be learning how to solve word problems. We're going to start with a quiz to test your knowledge.

Then we're going to look at today's star words.

We're going to look at some word problems. We're going to do a talk task.

We're then going to answer the word problem.

Then it'll be your turn to have a go at an independent task and we'll review the answers together.

And finally, there'll be a quiz to see what you've remembered.

So let's get started.

Pause the video now to complete your starter quiz.

Welcome back.

Let's have a look at our learning today then.

So we're going to do the star words.

We're going to do my turn, your turn.

So remember to repeat after to me.

Part.

Whole.

Unknown.

Known.

Add.

Subtract.

Brilliant, let's have a look at our learning for today then.

So our new learning.

We've got a question.

I'm going to read out the question and we're going to look at what key information we've got.

At this stage, we're not going to solve this question.

Question one.

Sam measures some wood to build a bench.

He has a plank of wood measuring 87 centimetres.

He cuts 21 centimetres off.

How long is the plank of wood now? Firstly, let's have a look at our key information here.

I can see in bold, we've got the plank of wood measuring 87 centimetres.

I can also see in bold that he cuts 21 centimetres of it off.

What I want you to think about is what do we know and what we don't we know about this question? Have three seconds thinking time.

What do we know? What don't we know about this question? Okay.

Well, what we know is we know that the plank of wood is 87 centimetres long until he cuts 21 of it off.

21 centimetres off, I should say, sorry.

What we don't know is how long a plank of wood Sam has been left with.

So if we think about this using our part, part, whole model, we know the whole.

We know the whole was 87 centimetres.

We know that 21 centimetres of those have been cut off.

What we don't know is that our unknown is what Sam is remaining with, what length of wood of the plank of wood Sam is left with.

This is our unknown value.

So this is what we need to find out to be able to answer that question.

Let's have a look at another example before we have a go at solving these equations, okay? So question two.

An apple weighs 35 grammes and a banana weighs 58 grammes.

How much do both fruits weigh in total? I'd like you to have a think.

What do we know about the question? What don't we know? Give yourself three seconds thinking time.

Now, let's have a think.

We know the weight of our apple.

It's 35 grammes.

And we know the weight of our banana.

It's 58 grammes.

The unknown in this question is how much they weigh when they're put together.

So if I think of it as my part, part, whole, this time, I know both parts.

I know the apple is 35 grammes and the banana is 58 grammes.

What I don't know is what they are when they're put together.

The weight in total.

So I would need to work that out to answer that question.

Let's have a go at today's talk task.

We will solve those equations after our talk task.

So your talk task today.

Match the questions to the correct bar models.

You've got four questions and four bar models.

You need to really carefully read through the questions and look really carefully at those different bar models before you match them.

Remember to use our say it out loud.

This bar model matches this word problem.

Pause the video now to have a go at today's talk task.

Okay, welcome back.

Well done for that.

You've worked really hard so far in this session.

We're going to have a look now at how they match.

So let's read question one.

An orange weighs 62 grammes and a peach weighs 34 grammes.

How much do both fruits weigh? Matches with this bar model here 'cause I can see my orange weighs 62 grammes and my peach weighs 34 grammes.

My question is how much do they both weigh? So I need to work out the value here of them both together.

Let's read our second question them.

Max has 60 millilitres of medicine.

He drank 30 millilitres.

How much medicine is left? So we've got our 60 millilitres and our 30 millilitres, how much is left matches with this bar model here because Max has that 60 millilitres but he's drunk 30 millilitres of it.

We need to find out how much is left by finding out the missing value that would be here.

Next question then.

Lisa measures some rope to build a swing.

She has 62 centimetres of rope.

She cuts 34 centimetres off.

How long is the rope now? Matches with this bar model here because she has 62 centimetres of rope.

She's already cut off 34 of those but our missing value, the value we need to find out would be here because we need to know how long the rope is now.

And our last question says a can of fizzy drink costs 60p and sweets cost 30p.

How much do they both cost? So let's see.

This links with this bar model here because our can of fizzy drink costs 60p and our sweets costs 30p.

We need to find out the total amount of them all together by finding out this missing value here.

Well done to those of you who got those correct.

It really helps when we look really carefully at that key information before we match them.

Okay, we're going to move on now to our develop learning.

The same questions we looked at in our new learning but we're going to look at how we solve them next.

So we have the same question.

I'm going to read it out to you again, looking at that key information and then we're going to look at our bar models.

Sam measures some wood to build a bench.

He has a plank of wood measuring 87 centimetres.

He cuts 21 centimetres off.

How long is the plank of wood now? So if we look at our bar model, we knew the whole.

The whole was 87 centimetres and we knew one of the parts was 21 centimetres.

What we needed to find out and know is this unknown here in red.

What was that missing number? So in order to do that, we need to do 87 centimetres take away 21 centimetres.

So the way that I did this was I wrote 87 centimetres take away 21 centimetres down.

I then thought back to the strategies that we used earlier in our unit.

But I thought I know, 21 could be partitioned into 20 and one.

So I could count back 20 from 87.

Let's do it together.

87 in our heads, we're going to count back our tens twice.

77, 67.

I then need to count back one more because I've partitioned 20 into 21.

So 67 in our heads, count back one.

66.

And I have to remember unit of measure is a centimetre.

So use the strategies that I've learned earlier in our unit to help me answer this word problem.

Let's have a look then at our second question.

Our second question said an apple weighs 35 grammes and a banana weighs 58 grammes.

How much do both fruits weigh? So I've got my bar model here.

I've got my banana here, which weighs 58 grammes.

I've got my apple here, which weighs 35 grammes and as I said earlier, we didn't know our whole.

That was our unknown, so we need to do something to work it out.

We need to do 58 add 35.

Let's see how I did this.

So in order to do this, I've written 35 plus 58 grammes.

Now, what I did was I knew 58 grammes is quite close to 60.

So I'm going to count up in my tens six times from 35 and then adjust my answer.

So I want you to do that with me now, okay? We're going to put 35 in our heads and we're going to count up six tens and see where we get to.

So 35 goes into our heads.

45, 55, 65, 75, 85, 95.

Stop, because we've counted six times.

And up to 95 grammes.

But I know that I've taken, I've added on, sorry, two too many.

So I now have to take away two from 95 to get me back down to 93 and my answer.

So our answer is 93 grammes in total.

It's now time for your independent task.

Let's have a look there.

Okay, today you have two different slides with some questions on them.

What I want you to do is read through the questions and have a go at solving them.

Remember to use those strategies that helped us and remember, you can use a bar model or even a part, part, whole model to help you out today.

Once you've had a go at those questions, we'll go through the answers together.

So pause the video now to complete your task.

Okay, welcome back.

We're going to work through the answers together then.

So let's have a look.

Question one.

Ellie baked a cake.

She added 55 grammes of flour, then she added 35 grammes more.

How much flour is there now? So I know my key information was 55 grammes plus 35 grammes.

In total, there would be 90 grammes.

Question two.

Anna had 33 pounds.

She spent 17 pounds on a toy car.

How much money does she have now? So I've got my 33 pounds and she's already spent 17, so I need to take it away to give me 16 pounds.

Next question, question three.

Lisa measures some wood to build a toy train.

The train, sorry, the train needs to be 80 centimetres long.

She has 62 centimetres of wood.

How much more wood does she need? So I've got my 80 centimetres.

I need to take away my 62 centimetres.

That would give me 18 centimetres.

So she needs 18 more centimetres of wood to build her toy train.

Question four.

A packet of crisps costs 55p and a bottle of water costs 39p.

How much do they both cost? So I need to work out the total amount.

So 55 p add 39 p equals 94 p.

Question five.

Jay had a paddling pool.

It has a capacity of 90 litres of water.

There is 44 litres of water in Jay's paddling pool.

How many more litres of water can Jay add to his paddling pool until it is full? Let's have a look.

So we've got 90 litres.

We want to take away 44 litres and that would give us 46 litres.

Question six.

Alice walked 58 metres to her bus stop.

And then walked 35 metres to school.

How far did she walk all together? So she walked 58 metres and then she walked 35 metres.

So I need to add them together to give me 93 metres was the distance that Alice walked all together.

Well done for working so hard today! I'm very, very impressed.

Pause your video now to have a go at the final quiz and answer a few questions based on what we've been learning today.

Thank you very much.

I'll see you again soon.

Bye.