Lesson video

Hi everyone, Mrs. Sawyer again.

At the end of the last session, I left you with this activity.

How did you get on? We had a look at the first one together.

The second one, 1/8 of the cubes are yellow.

If there is one yellow cube then there must be seven blue.

Your representation might look like this.

But as long as there are eight cubes, one in yellow and seven in blue, then you're right.

But the last example, 1/10 of the cubes are yellow.

If there is one yellow cube then there must be nine blue cubes.

Your representation could look like this.

Again, as long as there is one yellow and nine blue, then you are right.

Well done with those.

In today's lesson, we will be building on previous learning and looking at part-whole relationships by identifying fractions of set.

Here's some of the language we will be using in this session.

I have 12 biscuits in my biscuit jar, this time, this is the whole.

Just like in previous lessons, you looked at different shapes, paper strips, Lego blocks, or even containers that represented the whole.

This time, my 12 biscuits are the whole.

I'm going to share these between three plates.

Has my whole changed? No, my whole is still the same 12 biscuits, but now they've just been shared between three plates.

Let's describe what's happened to the biscuits.

The whole has been divided into three equal parts.

One plate of biscuits is 1/3 of the whole.

Does it matter which plate of biscuits I select to show one third of the whole? Let's see, I could select the middle plate.

Is it also a 1/3 of the whole? Can you explain that using the stem sentence above? Pause the video and have a go.

How did you get on? You're correct.

These biscuits also represent 1/3 of the whole.

How about the last plate of biscuits? Is that also one third? Yes, you're correct.

It is.

What do you notice with these images? What's the same and what's different to the previous slide? Do each of the plates still represent 1/3? Pause the video and have a think, or maybe talk to somebody else in your house.

Come back when you've made a decision.

The biscuits are arranged differently on each of the plates, but there are still the same amount of biscuits on each of the plates.

Let's say the sentence together.

One plate of biscuits is 1/3 of the whole, because the whole has been divided into three equal parts.

And one part is 1/3 of the whole.

This is 1/3, this is 1/3 and this is also 1/3 of the whole.

Now I'd like you to pause the video and gather 12 items. I'm going to use counters like you can see on the screen, but you could use 12 pieces of pasta or maybe even make your own counters out of pieces of paper.

Come back when you're ready, Let's have a look at this concept using my counters.

Here, I have 12 counters, although they're not in a box or a jar, I can still call these the whole.

I'm going to explore dividing my whole into different number of equal groups, the parts.

The first number of groups I'm choosing is two equal groups.

Let's use these stem sentences to describe what happened to the whole and how I can describe the parts.

Let's say them together.

The whole has been divided into two equal parts.

One of these parts is 1/2 of the whole.

This is a half, and this is also a half of the whole.

The denominator is two because we have two equal groups.

The numerator is one, because one part is selected.

Now I'd like you to pause the video and make your own two equal parts.

You can use the stem sentences again to help you.

This time, I'm going to divide the whole into three equal parts.

But before I do this, I'd like you to have a go.

Can you go and divide your objects into three equal parts? Pause the video to give yourself time.

How did you get on? Let's see if yours looks like the image that I've created.

Now let's use the stem sentence together to describe what's happened to the whole and how we can describe the parts.

The whole has been divided into three equal parts.

One of these parts is 1/3 of the whole.

This is 1/3, this is 1/3 and this is 1/3 too.

The denominator is three because we have three equal parts.

The numerator is one because one of the parts is selected.

Can you guess the number of groups we're going to create now? Pause the video and tell someone.

You're right.

This time we are going to divide the whole into four equal parts.

But before I do this, I'd like you to divide your objects into four equal parts.

Pause the video to give yourself time to do that.

How did you get on? This time, we have created four equal parts.

And so each part is 1/4 of the whole.

As we learned before, 1/4 has a special name, which is a quarter.

Let's use the stem sentence together to describe what's happened to the whole and how we can describe the parts.

Only the start of the sentences have been given to you this time.

Can we say them together? The whole has been divided into four equal parts.

One of these parts is 1/4 of the whole.

This is a quarter, this is a quarter, this is a quarter and this is a quarter too.

The denominator is four because we have four equal groups.

The numerator is one because one of the parts is selected.

Now what can you see? What do you think I'm trying to do here? I'm trying to create five equal groups.

Can we find a 12 into five equal parts? Pause the video and have a think.

Maybe talk to someone else in your house and try it with the counters.

Come back when you're ready.

What have you discovered? Let's have a look if it's the same as what I've noticed.

You're right.

12 cannot be divided into five equal parts because the parts would be unequal.

Watch what happens.

We can share up to 10 counters out to keep the groups equal, but what will happen to those two that are left out? I can carry on sharing them, but what is the problem with this? Pause the video and explain to someone.

You're right, two of the parts will have three counters and the other three parts will only have two counters in them, which make unequal groups.

I'm sure you'll agree with me that we don't have unequal groups in fractions.

Is there another way you could explain? The whole, which is 12 counters cannot be divided into five equal parts because five is not a factor of 12.

Now let's think, what's the next number of groups that I could try.

Six.

Can I create six equal parts? Can we divide 12 counters into six equal parts? If you know the answer already say it out loud, and then you can pause the video and try it with your 12 items. Were you right? Let's have a look.

We can say the stem sentence together to describe what's happened to the whole and how we could describe the parts.

The whole has been divided into six equal parts.

One of these parts is 1/6 of the whole.

This is 1/6, this is 1/6.

In fact, each of these equal parts represents 1/6 of the whole.

The denominator is six because we have six equal parts.

The numerator is one because one of these parts is selected.

Can we divide 12 into seven, eight, nine, 10, or 11 equal parts? To help you explain this, you could use the sentence starter on the screen.

First let's try and make seven equal parts.

Seven cannot be divided into equal parts because the parts would be unequal.

Five of the parts would have two counters.

And two of the parts would have only one counter.

Is there another way you could explain it? The whole, which is 12 cannot be divided into seven equal parts because seven is not a factor of 12.

How about eight, nine, 10, or 11? Pause the video and have a think or try it out.

Come back when you're ready.

What did you think? Were you able to use the sentence starter? I explained it in this way.

12 cannot be divided into eight, nine, 10, or 11 equal parts because they are not factors of 12.

What could be my next number of groups? Can you tell me out loud? Well done if you said 12.

Let's have a look and save a stem sentence together.

The whole has been divided into 12 equal parts.

One of these parts is 1/12 of the whole.

This is 1/12, this is 1/12, and this is 1/12.

In fact, each one of these parts represents 1/12 of the whole.

The denominator is 12 because we have 12 equal parts.

And the numerator is one because one of the parts is selected.

Let's summarise.

This is how we divided 12 into two equal parts to make halves.

Three equal parts to make thirds.

Four equal parts to make quarters.

Six equal parts to make sixths and 12 equal parts to make 12.

And here's your practise activity.

You can have a go at exploring yourself.

Find 16 objects around your house.

These could be anything such as pencils, beans, buttons, or dry pasta.

Investigate by making equal parts, trying to be a systematic as you can.

Each time you've grouped your objects, draw a picture and label one of your groups with the correct fractional notation and its name.

Here's an example I made earlier using the number 12.

I wonder how many different fractions you can find using your 16 items. Have fun.

Bye.