# Lesson video

In progress...

Hello everyone, and welcome to Maths with Ms. Dobrowolski.

In today's lesson, we'll be looking at comparing capacity.

Let's have a look at today's lesson agenda.

First, we'll be learning about nonstandard units.

Then we'll have our talk task.

Then we'll be comparing capacity with nonstandard units.

For this lesson, you will need a pencil and notebook.

If you don't have these items, pause the video now and go get them.

Super! Let's get started.

So, here we have my friends, the dwarves, and they're trying to decide how best to fill up their cups for dinner.

They have these two jugs, which jug do you think the dwarves should choose to make sure they can pour the most drinks? Mmh, which of these jugs can pour the most drinks? It's a little bit hard to tell because they're so similar in size.

One way we can check is by filling up cups with the same contents of each jug and seeing which one feels the most cups.

So the cups have to be the same size and we have to make sure we fill each cup to the brim, to the tippy top, otherwise it's not fair.

So what we're measuring is capacity.

Capacity, the amount a container can hold.

Super! So the capacity of the first jug is, count with me, one, two, three, four, five, six, seven cups.

So the first jug can fill approximately or about seven cups.

The second jug let's take a look.

The second jug can fill approximately, one, two, three, four, five, six cups.

So which jug has a greater capacity, the first jug or the second jug? Mmh, well, it looks like it's the first jug because the first jug can fill seven cups, whereas the second jug, can only fill six cups.

So the first jug has a greater capacity.

We can also measure capacity using a different nonstandard unit.

The first time we used cups, but maybe this time we'll use water bottles.

So the first jug can fill three water bottles or approximately just about three water bottles.

And the second jug can only fill two water bottles.

So which jug has a greater capacity? Again, it's the first jug because it can fill more water bottles.

It has a greater capacity.

So for your talk task, I want you to have a look at this jug that I've put on the screen.

And I want you to make an estimate about how many cups can the jug hold.

And I want you to do the same for the water bottles.

So for example, I think I would say, I estimate the jug holds about 10 cups, right? That's how many cups I think this jug holds.

And then you would do for the same with the bottles.

So go ahead, make an estimate and make sure your using that mathematical language and when you're done, resume, so we can talk.

Super! So, hopefully you've said that I estimate the jug holds about cups.

Remember it doesn't have to be an exact answer 'cause you're making an estimate.

The point of this is that your estimate has to be sensible.

If you said something like, I estimate the jug holds about one cup, well, that's maybe a little, that's too small because we know that this jug is bigger than the cups so it can definitely hold more than one cup.

Similarly, if you said the jug has a capacity of about one bottle, that's also not a sensible estimate because we can tell just by looking at the jug, it has a great capacity that's more than one bottle.

We can fill more than one bottle with that jug.

Super! So let's have a look at comparing the capacities of three containers.

So I have these three teapots here and this glass you see on the screen is equal to one unit.

So let's see, how many units do I think each of these teapots can hold? Well, I think that the red and blue striped teapot can hold four units.

So now what I want you to do is pause the video and I want you to have to think, how many units or approximately how many units can each teapot hold? Remember to use the full sentence.

I think the teapot can hold units.

Pause the video and have a go.

Super! So I said that the red and blue teapot can hold about four units.

I can see that the yellow teapot is a little bit bigger.

It probably has a greater capacity.

So I think the yellow teapot can hold six units.

And then the green teapot, well I can see that that one is even a bit bigger than the other two.

So I think the green teapot can hold about 10 units? Yeah, just about.

So which container has the greatest capacity? Well, if I said that the green teapot can hold 10 units, which was more than the other two, then the green teapot has the greatest capacity.

It can hold the most units.

Which teapot has the smallest capacity? You tell me.

Yeah, I agree.

I think the red and blue teapot has the smallest capacity because it can hold the least units.

Now for this independent task you'll have to get a few items. So I'm going to show you how to do this.

It's very important that when you're handling some delicate items like glass, you ask an adult.

So watch me, I'm going to show you how to complete this independent task.

Super! I have my four containers here and I will use this glass as my standard unit.

Again, when you're completing this independent task, make sure you ask an adult for help in order to get these items. Now, one glass then is equal to one unit.

First, for each container, I need to make my prediction.

So I predict that this jug can hold one, two units.

I predict that this jug can hold two units.

So I'll write that in my notebook.

And now I'm actually going to test my prediction.

So remember when we're filling this, we need to make sure we fill all the way to the brim, otherwise it won't be fair.

So, let's see.

That's one unit and I can still put a little bit more into here.

And again, we feel all the way to the brim, otherwise it's not fair.

I actually can put a little bit more in there, that's not to the brim.

Okay.

So that's two units and I think I can put a little bit more.

Oh, it's already full, so really my jug could only fill two units.

Super! So, you might've gotten a lot of different kinds of answers depending on what kind of containers were in your home.