(bright upbeat music) - Well, good morning, my magnificent mathematicians.

I'm super excited to be with you this morning because we are going to have so much fun today learning more about math and growing our brains.

And today, I have my amazing kiddos, Hayden and Hallie here with me.

We're going to investigate volume.

But first, let's head over to the chalkboard and check our understanding of dimension.

Now, a dimension is the way that we measure the size of something.

It could be the length or the width, or even the depth of something.

And let's start with 1D.

When we take a 1D measurement, we're only measuring how long something is.

And I bet you've had a 1D measurement taken at the doctor's office.

The doctor doesn't really want to know how wide or how deep you are, they just want to see how tall you are to see if you're growing so they measure your height.

Hayden, Hallie, can you all think of other examples of 1D measurements?

- Whenever I'm on a race, I only think one dimension, the length of the race.

No one talks about how wide or deep the race is.

That doesn't even make sense.

- That's funny and you're right, that doesn't make sense at all.

Hallie, how about you?

- I was thinking about the water park and how they measure how tall kids are to see if they can go on the big slides.

- Oh, that's a perfect example.

Great job , you all.

So, let's talk about 2D.

We measure in two dimensions all the time.

Think about different rectangular objects around your home that need to be measured like a picture frame that you want to hang on the wall.

And last, we're going to investigate volume.

Now, volume is a three dimensional concept.

Now, you can draw things that just look 3D but if something is really 3D, it has depth and it takes up space.

So in math, when you're measuring in 1D, you're only measuring length.

When you measure in 2D, you're measuring two dimensions, length and width which can give you the area or the surface of something.

And then when you measure in 3D, you're measuring three dimensions.

Length, width and depth.

Okay, let's look at a real example of this.

Measuring volume is different because you start thinking about the inside of something.

So, look at this 3D cube.

This cube has length and it has width and it also has depth.

The volume is the inside.

So, think about filling the cube, the inside part with something like this pasta.

(pasta crunching) To see how much space is in the cube, we would measure its volume.

Now, volume is measured in unit cubes.

And since the dimensions of our unit cube are in inches, we measure the volume of the big cube in one inch cubes.

Okay.

Hayden and Hallie.

I see that you have been working hard to see how many of these one inch cubes it would take to fill our cube completely without any gaps because that would give us our volume.

So you're getting pretty close, but you've got a few more.

You two finish that cube.

I'm going to use the math formula that I know and then we'll check what you get with the answer that I get and see if our answers match.

Okay?

- 61.

- 62.

- 63.

- 64.

- Okay, so I plugged into my formula and I got 64.

How many did you get?

- 64.

- You got 64 too?

- Yeah.

- He stacked perfectly and there are no gaps in it.

- Okay, no gaps because that's really important when we're measuring volume.

We want to make sure that our little unit cubes take up and fill up that whole space.

Now, here's the math formula that I used.

You can find the volume of a cube by multiplying its length times its width times its depth.

So, I did four because it was four inches long times four again because it was four inches wide times four again because it was four inches deep.

And I got 64 cubic inches.

And that's the same thing that you got when you added all of those little one inch cubes together.

- Yeah.

- Now, that would take a really long time.

So, I think we can see how the formula even though this lets us picture it.

- Yeah.

- The formula is much, much better way to find volume, right?

- Yeah.

- Okay.

But you all thanks for the example.

That was amazing.

Okay, that is all the time that we have for today.

This was fun, right?

- Yeah.

- You all did great.

Thank you so much for joining us today to investigate volume.

I hope that you have an amazing day today and we'll see you next time on Rise and Shine.

Bye.

(bright upbeat music)