- Hi third graders.

My name is Ms.

Turner and I'm here with Riley and Brinkley.

We are so excited that you decided to join us for this math lesson.

I'm so happy that I get to be your math teacher for the next hour.

Since we'll be together for a little bit, here's some facts about me.

I teach third grade at Old Mill School in Wall Township.

I love my school and my class.

I miss them so much.

But we are making the most of everything, over video chatting.

I have two dogs named Riley and Brinkley.

They will be my helpers today.

I love sea otters.

I love them so much that I wrote a book about them.

It's called, "Close at Heart: A Sea Otter Story."

I also traveled to Monterey, California last year and got to see sea otters in real life.

Perhaps most importantly, what all of my students know about me, is that my favorite subject is math.

(cheering) I tell all of my students on the very first day of school, that it's all part of my evil plan, (devious music) to make you love math as much as I do.

So, since you're my students for the next hour, it's my sincere hope that I can make you love math a little more than you already do.

(cheerful music) I love how math really is all over the place.

Math is on paper.

And math takes up space.

I see subtraction when Brinkley eats his food.

I see addition when together, things get glued.

I see multiplication in equal groups of fruit.

I see speed when my dogs run their favorite route.

I see comparisons with my sea glass jars.

I see distance when I look up at the stars.

I see an array when my cupcakes cool.

I see math in and also out of school.

Did I mention that I like to rhyme?

I love rhyming.

Now since I'm teaching my favorite grade, my favorite subject, it only makes sense for me to teach you my favorite thing.

Area and perimeter.

So today what we're going to do is, we're going to explore a little bit about what area and perimeter are and how they apply to real-life situations.

Here are some materials you'll need for today's activities.

Some materials you will need for this lesson include: paper, a pencil, and about 20 or 30 square objects.

These could be things like crackers.

Cereal, or non-edible things, like a piece of paper, a Lego, or a block.

If you have other square items that are similar to this, absolutely grab them.

If you need help gathering any of these materials, you may ask a trusted adult.

Collect these items.

Brinkley will let you know when 20 seconds are left.

(upbeat music) - [Child Voiceover As Brinkley] 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, nine, eight, seven, six, five, four, three, two, one.

- Now one thing that I really want you to know about me as a teacher, is that all I ever ask, is that you do your best.

Whether it's playing around with some materials from today, doing some equations, or yep, we're gonna have some singing and dancing later on.

I just ask that you have fun and do your best work.

I think we're gonna have a really great day today.

(upbeat music) When I went to high school, I was on the field hockey team.

At the start of every practice, my coach would tell us to run a perimeter.

What do you think that was?

What might it have looked like?

Well Riley and I are going to show you a perimeter, of our side yard and maybe you can figure out what it is my coach was telling us to do, when we did a perimeter before every practice.

Come, Riley.

(upbeat music) What observations did you just make?

What were we doing just then?

Did you notice that Riley and I walked around the outside of our side yard?

That's exactly what a perimeter is.

A perimeter is a distance around a figure.

In this case, it was our side yard.

Now, when I was playing field hockey in high school, it was the distance around our, not just our field hockey field, but it was the distance around our entire athletic complex.

When our coach told us to do five perimeters.

That was really hard.

We just came in from my side yard where we found out that a perimeter is the distance around the outside of the shape.

But right now, what we're gonna do together, is we're gonna figure out exactly what the perimeter is of my side yard.

So here I made a small digital version of my side yard.

You can see there's little Riley in there.

So what information do you think we would need to know, to figure out what the actual distance is, around the outside of my side yard?

What would we need to measure?

Yeah, we'd need to know how long the sides are.

So I went outside and I measured across and up and down and I saw that it was 25 feet across and 72 feet long.

So, but I only measured these two sides.

I forgot to measure these two sides.

Is there a way that I could still figure out how long this side is?

And how long this side is?

Yep, we can use what we know about rectangles.

We know that if this side is 25 feet, we know that this side will also be 25 feet.

If this side is 72 feet, this side will also be 72 feet, because rectangles are made up of two pairs of equal sides.

So now I have all my numbers.

What do I do now?

I have to figure out a total.

I'm combining them together.

So to figure out the total perimeter, I would need to add these numbers together.

So I'm going to start off by adding just some of them at a time.

So the first numbers I chose to add up, were 25 and 25, give me 50 feet.

So I added those two sides right there.

Next, I decide to add up 72 feet and 72 feet, giving me 144 feet.

But I'm not at my final answer yet.

I have two partial sums, which means I'm partially towards my answer, but not totally there yet.

So my last step to do, will be to add up 50 feet and 144 feet.

I did so, just there, giving me a total perimeter of 194 feet.

So, when we're finding a perimeter of an object, you have to add up all the sides.

Now I could sit here and keep telling you the definitions of area and perimeter and you could just listen to me speak.

But we don't wanna do that.

What we're going to do next, is we're going to try to incorporate some real fun into it.

When we start to incorporate more things like singing and movement into activities, it actually helps your brain remember it better than as if we were just saying the words.

So what we're going to do is, we're going to incorporate some songs and movement into perimeter.

But, I don't wanna just include me.

I figured I'd call some of my friends to help out.

(computer ringing) Hi class!

- [Group] Hi!

- Today we're here with third graders, all across New Jersey.

Let's give them a nice big hello.

- [Group] Hi.

- So today we're learning all about perimeter.

Do you wanna help me teach our perimeter song?

- [Group] Yes!

- Okay, great.

So third graders at home.

I want you to just listen and watch the first time.

Then you'll join us on the second round.

All right, five, six, seven, eight.

♪ Perimeter's round ♪ ♪ Perimeter's round ♪ ♪ Oh, oh, don't you know perimeter's around ♪ ♪ You add up all the sides ♪ ♪ You add up all the sides ♪ ♪ Oh, oh, don't you know, you add up all the sides ♪ All right, all together now.

♪ Perimeter's around ♪ ♪ Perimeter's around ♪ ♪ Oh, oh, don't you know, perimeter's around ♪ ♪ You add up all the sides ♪ ♪ You add up all the sides ♪ ♪ Oh, oh, don't you know, you add up all the sides ♪ Awesome, thank you so much for helping us out.

Bye, everyone!

- [Group] Bye!

- So thanks with the help of my students, we just learned a catchy tune to always remember that perimeter is around and to find the perimeter, you have to add up all the sides.

So here, I have an example of a rectangle.

There are four sides to it.

We see that perimeter is around.

To find the perimeter, you have to add up all the sides.

So in this case, it was seven centimeters, seven centimeters, three centimeters and three centimeters, giving us a grand total perimeter, of 20 centimeters.

Now, I have another shape in mind for you.

A triangle.

We haven't seen a triangle yet.

Can we still find the perimeter of a triangle?

Yes, because perimeter remember, perimeter is around.

So instead of having a rectangular shape here, we're just going to have three sides for that triangle.

Now what are we going to have to do to find out the perimeter of this triangle?

That's right.

We're going to have to add up all the sides.

But before, we had four sides, because our rectangle had four sides.

This time, we're only going to have to add up three numbers, 'cause there's only three numbers.

So we see perimeter is around the shape of this triangle.

Here, we're going to add up all the sides.

Three, plus three, plus three, gives us nine inches.

So, perimeter is not always just squares and rectangles.

I know a lot of our examples have been that.

But it can be the distance around any shape.

We saw the rectangle, the triangle.

Here we see this irregular figure.

And here, we see this other kind of a polygon.

So perimeter is distance around any kind of a shape.

Remember, perimeter is around and you have to add up all the sides.

So right now, we have this shape right here, this rectangle and we're going to use that song we just learned with the help of my students, to help find the perimeter of it.

Remember, perimeter's around.

Perimeter's around the outside of an object.

To figure it out, we have to add up all the sides.

So let's do that right now.

Let's make some observations about our rectangle.

We see there are four sides.

10 inches, four inches, 10 inches and four inches again.

So we have all of our sides.

Now we need to add our numbers up.

So, let's start off by adding our 10s.

10 plus 10, gets us 20 inches.

Four plus four, gets us eight inches.

Our last step.

Add up our partial sums, exactly.

20 plus eight, gives us 28 inches.

We just found the perimeter.

Get out your paper and pencil because, it's time for a pup quiz.

(barking) Complete the sentence.

Perimeter's around, perimeter's around.

Oh, oh, don't you know, perimeter's around.

You, what?

What do you do to find the perimeter?

That's right, you add up all the sides.

Well done, everyone.

Find the perimeter.

The perimeter of this shape is 22 inches.

You could've added up the numbers six, six, five and five in any order and you should've gotten 22 inches.

You're a rockstar!

All right, so let's pretend now, that instead of a field hockey field, we're at a basketball court.

(ball dribbling) And you're on the basketball team.

Your coach wants you to run around the perimeter of the court, to warm up for practice.

How many feet would you have to run?

To add up all the sides, you could've first added 50 and 50 feet to get 100 feet.

94 feet and 94 feet to get 188 feet.

Then you could've added up those two partial sums, to get 288 feet.

You could have of course added these numbers in a different order, but you still should've gotten that final perimeter of 288 feet.

Both Brinkley and I agree that you've been working very hard today.

It's time for a break.

Now this break might seem a little off character for me, because I'm a dog person.

It might seem completely random, but you bet, I can tie it into perimeter later on.

This is also one of my class' very favorite brain break.

So three T, this is for you.

It's time everyone, to run like the kitty.

- [Man] Awesome sauce!

- Run in place during this brain break.

(mumbles) to this stellar sauce.

♪ Everybody run like the kitty ♪ ♪ Run like the kitty, kitty ♪ ♪ Run like the kitty, kitty ♪ ♪ Run like the kitty, kitty ♪ ♪ Run, run, run, run ♪ ♪ Wait a minute ♪ ♪ Kitty, kitty kind of looks like a raccoon ♪ ♪ Maybe it's a beaver ♪ ♪ I don't know my animals ♪ ♪ Run like a raccoon, kitty ♪ ♪ Run like a beaver, kitty ♪ ♪ Run like a rabbit on the screen ♪ ♪ Run, run, run, run ♪ ♪ We'll be running anyway ♪ ♪ Maybe to the wizard ♪ ♪ (Mumbles) to be a unicorn ♪ ♪ That's a thing-a-ma-jiggy ♪ ♪ Run like the happy kitty ♪ ♪ Beaver, raccoon, something ♪ ♪ Run like whatever it is ♪ ♪ Run, run, run, run ♪ ♪ Run to the wizard ♪ ♪ Have some Swiss cheese ♪ ♪ Make sure that you say please ♪ ♪ Just like a running kitty ♪ ♪ Run like the kitty, kitty ♪ ♪ Run like the kitty, kitty ♪ ♪ Run like the kitty, kitty ♪ ♪ Run, run, run, run ♪ ♪ Run like the kitty, kitty ♪ ♪ This song is over now ♪ ♪ Sorry that it didn't rhyme ♪ ♪ I just needed to finish the words ♪ (dinging) - Did you all enjoy running like the kitty, kitty?

Do you see why that's one of my class' favorite brain breaks to do?

So right now, your heart rate might be a little bit up.

You're feeling very excited.

We're gonna try to cool it down a little bit, before we move on with the rest of our learning for today.

So right now, I want you to stick your finger out and we're gonna make a nice, big shape with a really big perimeter.

Take some nice deep breaths as you do this.

Watch your finger move around the shape that you're making.

Now make your perimeter a little bit smaller.

Take those deep breaths.

Smaller and smaller and smaller.

See how teeny you can get that right now.

How small of a perimeter can you make and still make it a rectangle?

Nice deep breath, make it a little bit bigger now.

Make some bigger rectangles.

Have that perimeter increasing.

A few more deep breaths.

Make the biggest perimeter you can make.

All right and we're going to move on with our lesson.

(upbeat music) Right here, I've used some masking tape, to mark off a very specific area of space, that I'm looking to fill up with Legos.

How many Legos do you think I will need to fill up this entire space?

What's a number that you think is way too small?

Yeah, it wouldn't be a little number like one or two Legos.

Now what's the amount of Legos that you think is way too big?

Yeah, a big number like 50, 100.

I heard someone just say 1,000.

Also, way too big.

So think for a minute.

What do you think is a realistic number of Legos that could fill up the inside of this shape?

All right, let's give it a try.

One.

Two.

Three.

Four.

Five.

Six.

Seven.

Eight.

Nine.

10.

11.

12.

13.

14.

15.

16.

Exactly 16 Legos.

16 square Legos, fill up the space that I had there.

If you came up with exactly 16, or a number close to 16, awesome job to you.

That was a little tricky.

I had to think a little outside the box there, to figure it out.

What we just did there, is we figured out the area of the object.

We had a shape and we had to figure out how many square units, each one of these is a square unit, how many of them would fit inside and we found out that it was exactly 16 of them.

When we have area, we're trying to figure out how many square units fill up a space?

Now we just have random Lego measurements for this right now.

Other times, when you're finding the area of a space, you might need to use an exact measurement.

Unit just kind of means, any kind of a thing that you might have.

What are some units you know that we measure things in?

Yeah, we could use square inches.

We could use square feet.

Or even square miles, if we're talking about a really big space.

But here, since it's not an exact measurement, we just call it square units.

Do you remember when we first got started, how I asked you to get some materials that looked like squares?

Some of you might have square Legos like I do.

You might have some crackers, or cereal, or pieces of paper.

Or maybe you have a bunch of some other kind of square object, that I didn't list.

If so, awesome!

It's time to get those out.

Just like we learned before, area is filled up with square units.

Right here, I have a super tiny area.

It has one, two, three square units.

Right now, I want you to make any kind of a shape, using your squares that you have.

I'm gonna make my own and you do the same.

Yours does not have to look the same as mine does.

There.

I have a... I don't know.

I might add a little bit more onto it to make it something that I actually recognize.

There, I have a, what do you think I have right now?

I think it could look like a house, or a star, kind of, I don't know.

Anyway, it's a nonsensical shape, that's not quite a square or a rectangle.

What does your shape look like?

Now to figure out the area of our shapes, we simply have to count up the squares.

So let's count them up together.

For mine, let's count mine, then you can count yours.

One, two, three, four, five, six, seven, eight, nine, 10, 11, 12, 13, 14.

My area is 14 square units.

Count up your area right now.

I'm curious how many square units it is.

All right, enough with this nonsensical shape right now.

I want to move on to something else.

I'm gonna move my Legos to the side.

Actually, oh actually I'll keep them as they are, because I'm going to modify them a little bit.

Going to add on just like that there.

A nice rectangle.

Oh, I like this rectangle.

It's nice clean lines and I want you to change your Legos, that way they make five rows of three, just like mine are.

Now as a really smart third grader, I bet you could come up with a way where I don't have to count up every single one here.

What do you notice about our shape?

Do you notice that it has equal rows?

And columns?

Remember, rows go side-to-side, like a movie theater.

Columns go up and down, like the columns of a house or building.

So because I have equal rows and columns, I can use multiplication.

So for this, I have one, two, three, four five rows and one, two, three columns.

Five times three, gives us 15 square units.

So this next example is just like the Legos that we just saw, but instead of three units across and five rows down.

We have three units across and six rows down.

I'm saying the word units, because we're not being specific with something like inches, or centimeters, or feet, or miles.

It's general, it's generic.

So I'm just using that word units.

So right now, I have all my little boxes inside.

But watch what happens next.

The boxes went away.

Even though there aren't little boxes there to tell me this is three units, this is six units, in rectangles sometimes we'll see, it just tells us the measurements.

Even though it doesn't show us the boxes, it's still three units.

We can trust that.

This is still six units down here.

So moving on to the next part, what we see here, oops I just scoot my picture over here.

To figure out the area, we would do just the same as we did before, when we're counting the squares.

When we were counting the squares, we could see that there were six rows of three.

Now here, even though the boxes aren't there, it's still six rows of three.

We can still use that multiplication, because when it comes to area, we multiply the length times the width.

That gives us the area.

So for here, I would do six times three, to give me 18 square units.

Now remember, we have to use the word square, when talking about area, 'cause we're referring to the inside.

It's actually all those little squares.

When it's perimeter, we're just counting straight lines along the outside.

It's not squares, it's just the edges.

So when we're talking about area, we have to use the label square thing, whatever it may be.

That could be units.

It could be inches, or centimeters, or miles, or whatever the measurement may be.

But for area, we have to use the word square, because it's really counting all the little squares inside.

(computer ringing) Hi, again.

Do y'all wanna help me teach the area song too?

- [Group] Yeah.

- You're gonna watch and listen the first time through and then we'll join all together.

Five, six, seven, eight.

♪ Length times width is area ♪ ♪ Length times width is area ♪ ♪ Length times width is area ♪ ♪ Area's the whole inside ♪ All together now.

♪ Length times width is area ♪ ♪ Length times width is area ♪ ♪ Length times width is area ♪ ♪ Area's the whole inside ♪ Thank you so much, class, for helping me teach these songs to all of New Jersey students in third grade.

- You're welcome.

- Thank you so much and hope to see you soon.

Bye.

- [Group] Bye!

- So here we have a rectangle and we're gonna remember our song on area, to find the area of it.

We remember, ♪ Length times width is area ♪ ♪ Length times width is area ♪ ♪ Length times width is area ♪ ♪ Area's the whole inside ♪ So right now, we're trying to figure out the area.

The whole inside of our rectangular shape.

But I notice there are four numbers on here.

Before, I just had two.

How many numbers do you think I have to multiply here?

Yeah, even though there are four numbers, it's still length times width.

Really do that motion with it.

Length times width is area.

So here I do three times seven, to find my area.

It doesn't say length times width, times length times width.

Just length times width, because remember.

We can use that multiplication, because there's really these imaginary little squares inside there.

Equal rows and columns, which make an array, which is what multiplication is.

So to find our area for this shape, we would do three miles times seven miles, gets us 21 square miles.

Very good.

Let's take a look at another example.

I'm curious your thoughts on this one.

Do you think we can use length times width, to find the area of this shape?

No, we can't.

Because this triangle isn't made up of equal rows and columns, like our squares and rectangles are.

This one is actually an equation you'll learn later on and so we're not gonna worry about that right now.

But for cases of area, and you think length times width, you are just gonna use that for squares and rectangles.

It's time for a pup quiz.

(barking) Complete the sentence.

Length times width is area.

Length times width is area.

Length times width is area.

Area is... That's right, area is the whole inside.

Thumbs up to you.

The kitty wants to run, run, run, run in this field.

How much area can the kitty run in?

The kitty can run in 30 square meters, because six meters times five meters, equals 30 square meters.

Meters can be abbreviated with m. True or false.

Area is when you add up the sides of a shape.

False, perimeter is when you add up the sides.

Area is when you multiply length times width.

Which rectangle has the bigger area?

That was a trick question.

They're the same area.

Nine times one equals nine square inches and three times three equals nine square inches.

What is the area of the figure?

Now you might be looking at this and thinking, "Ms.

Turner, this is not a square or a rectangle.

"We established before that we can only use "length times width with squares or rectangles."

That's correct.

But we can still figure out the area of this shape.

What do you think we could do?

This is not a square or a rectangle.

But how could we turn it into squares and rectangles?

Yeah, we could cut it up in different spots.

We could cut it up along here.

Or we could cut it along here.

I'm going to cut it along up and down, right here, just like that.

So now, instead of having one shape, we have two rectangles.

I'm going to call this one A. And I'm going to call this one B. So for A we would do, two times three equals six.

All right, let's take a look at B. Don't have any numbers on this side.

Not one there, oh I do have four times two and I'm sure to look at those numbers, they go all the way from one side to the other, one side to the other.

So for B, we would do two times four, gives us eight.

But I don't have my full area right here.

What can we do to combine these two areas together?

Yes, we have to add them up together.

So we'll combine six plus eight, to give us 14 square feet.

That was a bit of a challenge one there.

But even with these irregularly shaped objects, you can still use what you know about area to solve them.

You just need to break them up into squares and rectangles, to use length times width.

(upbeat music) All right, it is time for us to get out our squares again.

I decided to switch to some crackers.

I see that some of mine are not perfect squares, so I will just have to enjoy them for a snack later.

So right now, with your squares, whether you have your blocks, your crackers, your cereal, or whatever else it may be, I want you right now to get out, let's see, 16 of them.

(upbeat music) All right, so these crackers are now my square units that I will be building with.

Right now, I wanna show you how we can create a lot of different kinds of perimeter, with these same 16 squares.

So we're gonna really have to be looking out and making observations about them, as we've been doing this whole lesson.

You've been doing such a good job of that.

So right now, I want you to play around with your crackers, or squares, or blocks, or whatever you have right now, for a little bit and see what kinds of squares and rectangles, can you make out of them?

Have some exploring time right now.

(upbeat music) All right, so what I'm gonna do now.

Is I'm gonna try to make the longest rectangle, and the skinniest rectangle I could possibly make.

All right, I want you to do that with me right now.

I'm gonna try to line them up exactly.

(upbeat music) There we go, I have 16 of my crackers, all in a row together.

So my area for this would be 16.

Let's see what my perimeter is like right now.

One, two, three, four, five, six, seven, eight, nine, 10, wait a second.

I don't have to count the whole thing.

I know there is 16 edges on this side.

I know there are 16 edges on here.

16 plus 16 gives me, 32.

32 plus another two, gives me 34.

So oh, if it's long and skinny like this, I have a perimeter of 34.

Let's see if we can make another shape.

How about this time, we try making it still long, but not quite as skinny, 'cause we can't really get skinnier than having one square unit.

So let's try going for two right now.

So let's try making two rows of eight, with our crackers.

You make yours look the same as mine right now too.

All right, what's our perimeter now going to be?

We know there's eight along this side.

Eight along the top.

Two and two.

So that gives us 16 plus another two.

Oh my gosh!

What do you notice about this perimeter in comparison with our previous one, that was 34?

Yeah, it went down a lot.

Has me thinking, what do you think will happen if we try to make it even smaller?

Now remember, we're creating area, which is like multiplication, 'cause you know, length times width, gives us our area.

Does three times something give me 16?

Three, six, nine, 12, 15, 18.

No, it skipped over 16.

What about fours?

Four, eight, 12, 16.

Yes, four times four.

So right now, let's create four rows of four, using our blocks.

All right, now before we calculate the perimeter, do you think our perimeter's going to get bigger or smaller?

All right, let's see.

We have, one, two, three four.

Eight, 12, 16, yes our perimeter went down even more.

So what do you notice, when we had that long and skinny array.

The still long, but not quite as long and not quite as skinny.

And now we have this square shape.

What are we noticing?

We're noticing the longer and skinnier a shape is, the bigger the perimeter it has and the more square like it is, the smaller the perimeter it has.

All right, let's try this again with a different number of crackers.

So right now, instead of 16, actually you know what, I want you to pick a new number.

But it's helpful to pick a number that you can multiply a lot of numbers to get to.

Like 16, because you get one times 16, two times eight, four times four.

So you could do a number like 15, 20, 24.

You pick a number, it could be one of the ones I just said, but it doesn't have to be.

You pick a new number and I want you to see how many different arrays you can create out of it.

I'm going to do the same.

I ended up choosing the number 12.

So I ended up with three different arrays.

They all have the same area.

So now, let's take a look at each of these different rectangles, which all have the same area of 12.

One times 12.

Two times six.

Three times four.

Let's see how that perimeter changes, as how the crackers are arranged, changes.

Right here, I have my long and skinny one.

I have one row of 12.

My area we know is 12.

My perimeter is, 12 plus 12, gives me 24.

Plus another two, is 26.

A perimeter of 26.

Pretty big perimeter.

Based off what we learned before, do you think my perimeter's going to get smaller for these ones, or bigger for these ones?

So over here for this one, I have two rows of six.

I have six and six for my perimeter, which gives me 12.

Plus two, 14, plus another two, 16.

Ah, that perimeter did get smaller and I know what you're thinking, this one's gotta get smaller too.

So we had 16 over here.

Let's take a look over here.

Four and four is eight.

Three and three is six.

Eight plus six gives me, 14.

So, it did in fact, get smaller.

Not by much, but it did get smaller by a little bit.

Did you notice the same thing with your arrays?

Here's one way to really visualize area and perimeter.

Visualize a really big area, with lots of little perimeters around the outside of it.

This visual can help you to really see the difference between the two words.

As we've seen from this lesson, perimeter and area are very different, but they also have some things in common.

Right here, I have all these different items that go somewhere in our VIN diagram.

Some are just for area.

Some are just for perimeter.

And there are some things that the two have in common.

So I want you to first take a look at them all.

See if you can spot which ones might go in certain spots of the VIN diagram.

I bet you guys all know where this goes and which ones do we add up all the sides?

Sometimes I'll tell my students, sing this song to help you remember, what the words mean, so.

♪ Length times width is area ♪ ♪ Length times width is area ♪ ♪ Length times width is area ♪ ♪ Area is the whole inside ♪ Then we have, ♪ Perimeter's around ♪ ♪ Perimeter's around ♪ ♪ Oh, oh, don't you know, perimeter's around ♪ ♪ You add up all the sides ♪ Yes, you add up all the sides goes with perimeter.

And just like we also sang with our song.

Length times width goes to area.

Which one of these is measured in square units?

One is measure in units, the other is square units.

Yes, square units is for area, because remember, it's all those little squares inside.

Units is perimeter, 'cause that's just the straight line from the outside.

Which of these things is used with shapes?

Both area and perimeter are used with shapes.

The inside of a room.

What would that be for?

Yes, that would be for area, 'cause area's the whole inside.

Whereas, the outside of something, like a field, is for perimeter.

Now which of these is used in real-life situations?

Both area and perimeter are used in real-life situations.

Great thinking, everyone.

Let's take a 30 second break at the beach.

(upbeat music) Now you might be thinking, "That's great, Ms.

Turner.

"With perimeter we add up all the sides.

"With area, there's all these "little imaginary squares inside.

"But how exactly does that apply to real-life?"

Thank you for asking that.

I'm about to show you some examples.

(upbeat music) We were just wondering about some real-life situations of perimeter and area.

So I decided to bring you out here to my backyard, where we have our garden, for raspberries and blueberries.

Now they might be a little tough to see, because they're growing quite a lot right now.

But around the outside, is a rectangle.

That rectangle is used to contain the dirt inside.

When we were building it, we had to think, "All right, "how much space do we have in total?

"So how much space can we put our garden in?"

Area.

We had to think, "All right, what's the outside "of it going to be?

"How much wood would we need?"

Perimeter.

So these real life situations of perimeter and area, were applicable to our garden that we have.

(upbeat music) So I was just looking up pictures of brownies and I found this one, 'cause I was going to show you about how the inside is area and the outside is perimeter.

But then I came across this photo.

Have you ever seen a brownie pan like this before?

I haven't.

This changed a lot of things about the brownies.

Think of what you know about area and perimeter.

Think of what these brownies would look like after they come out of the pan.

How would this change area and perimeter?

By having those little inserts in the brownie pan, they're taking away area, from the brownies.

By putting those inserts in there, they're adding more edges.

Which is adding more perimeter.

Huh, that's really cool!

(upbeat music) I bet there are a lot of squares and rectangles in the room that you are in right now.

Take a moment.

Look around your room.

Oh my gosh, I see so many already!

Do you as well?

Let's take a few minutes, so you can look around your room and see just how many squares and rectangles you can find.

(upbeat music) Did you find a lot of examples of rectangles too?

I see some in my windows over there.

Oh I see the vent right there.

Doorway, picture frames, books.

Oh yep, right there, the light switch too.

My piano, my laptop, the phone right there.

The TV you're watching right now.

Those are all rectangles, that you could solve, oh yes, and yes a good eye.

The picture frame behind me is also a rectangle.

So you could find the area of those things by multiplying length times width and we're gonna take a look at some more objects in my house and we are going to figure out the area of them, using that same formula.

A few of you noticed before, that you have some rectangles on your floor.

Your floor in your room may be one and also some rugs.

So this right here, this black rectangle, is my front door and I'm looking to put a rug in the front of this space.

I want it to be just right for this space.

So I have to think of how much space is being taken up here?

Ask yourself, "Would this be area, or perimeter?"

Yes, I'm talking about area right now, because I'm talking about all this space that's being taken up.

I'm not talking about the outside space around this shape.

I'm talking about what's inside and that is area.

So let's first figure out the area of this shape.

I have my 10 feet across and seven feet long.

So I do 10 feet times seven feet, to give me 70 square feet.

All right, great.

So I wanna make sure that I'm picking a rug that's not too big for this space, not too small for this space, but is just right for my door entrance way.

So let's start off with this first rug that I happen to have and let's see if it's a good fit.

So this rug, is eight feet by nine feet.

What do you notice, when looking at this rug, by the front door?

Yeah, it's a little big.

Do you notice it's actually going off the floor?

This rug wouldn't fit in this part of my house.

It's way too big and the square footage, it's eight times nine, that's 72.

That's actually bigger than my space that I have here.

I had to keep it from going off the page.

So unfortunately, this rug's not going to work.

Let's try another one.

Here's my next option.

This rug is one foot by two feet.

What do you notice?

Yeah, the area of this rug is only two square feet.

It's way too small.

If someone's walking through my front door, they might accidentally kick the rug to the side, 'cause it would just kind of fling across the room.

This rug is too small for the room.

If someone is coming in the door over here, or over here, they wouldn't get a chance to wipe their feet.

So this rug will not be helpful to me either.

Let's try one more time.

My last option is this rug, right here.

So notice this rug isn't too, too big, like the first one.

It's not going out of the floor space.

It's not too little.

I think this rug is just right.

It's a good size in front of my doorway.

I think it'll be good for guests and most importantly, it fits inside the room.

So when people are thinking of rugs in spaces, they're actually thinking of area.

They're thinking of the size of it.

Of course the design is important too, but they also want to think of how big the rug needs to be for the space.

Quite a few of you mentioned that you saw some rectangular picture frames, inside your homes.

I have some here too.

Actually, feel a little bit of re-decorating.

I'm hoping that you can help me out with that.

What do you notice about each of these picture frames?

What do they have in common?

Some of you may have said they're all rectangles.

I know they're a little bit at an angle right now.

Here's a head on view to help you visualize the rectangles.

So they're all rectangles, but what makes them different?

What do you think Riley, what do you notice?

Yeah, some are bigger than others.

One's really long and skinny.

This one's definitely the biggest.

This one's like the smallest of the bunch.

So each one of these picture frames is designed for it's own spot inside my house and I'm going to need your help to figure out the perfect spot for each.

Here are my three picture frames, with their lengths and widths.

Think about what we've learned about area.

Make observations about these photos and then we're going to look at the different places in my house where we could put them.

These are the three different wall spaces where we are looking to put pictures.

Make observations.

Then we will look at each wall individually, for the perfect picture.

The middle picture only says three feet in each direction, because sometimes we like to put a lamp on that table.

Here are the measurements for this wall, where we're looking to put a picture.

Which picture do you think we should put on this wall?

Any of the pictures would've fit on this wall, but since this wall is the largest space, we decided to put the largest picture.

Which picture do you think we should put on this wall?

Notice that there's only room for a picture that goes at most, three feet in both directions.

This is because sometimes we like to put a lamp on that table.

This was the smallest wall area for a picture.

So we needed to use the smallest pictures.

None of the other pictures would've fit, since we sometimes like to put a lamp on the table.

Which picture do you think we should put on this wall?

The dogs agree.

Since this is a long and narrow wall space, the long and narrow picture, would best suit this space.

Hi, third graders.

(upbeat music) I wanna thank you so much for joining us today, for this hour of learning.

Here's a recap of what we did today.

We made some observations.

We learned some new songs.

♪ Perimeter's around ♪ ♪ Perimeter's around ♪ ♪ Oh, oh, don't you know, perimeter's around ♪ ♪ You add up all the sides ♪ ♪ You add up all the sides ♪ ♪ Oh, oh, don't you know, you add up all the sides ♪ We explored perimeter and area.

We had some hands on activities.

We learned another song.

♪ Length times width is area ♪ ♪ Length times width is area ♪ ♪ Length times width is area ♪ ♪ Area's the whole inside ♪ And we saw that area and perimeter are all around us.

So again, I wanna thank you so much for spending this hour with us together.

I especially wanna thank the real MVPs, Riley and Brinkley, for really just being awesome.

We hope that you enjoy the rest of your day.

Remember to keep an eye out for area and perimeter.

It's all around us, all the time.

Have a great day and happy learning.

Here you go, Brinkley.

Good boy.

Riley, good girl.

Bye, everyone.