# What is the Perimeter?

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## Objective

SWBAT create and solve real world problems involving the perimeter of a polygon

#### Big Idea

I can create polygons and find the perimeter by using the unit squares on my paper

## What is Perimeter?

10 minutes

Everything we do is connected, and so I love when we get to add another layer of learning and knowledge onto what we already know. We learned about fractions, which helped us with understanding number lines, and then we learned about measurement! Who can tell me what they know about perimeter? What does it represent?

One trick for solving perimeter problems quickly is that I always remember to add up all the sides. I think about it as perimeter has the word “rim” in it, and so I need to go around the outside “rim” of my object.

There are things we can do, like circle the number or put a check mark next to it as we add, to keep track of our work and stay on track! Who can help me with these 2 examples?

## Warm-Up Activity

10 minutes

Today when you return to your seats I want you to try out the tricks we just talked about as you solve these perimeter problems. Remember that we don’t all use the same tricks at the same time, so I want you to find the one that works best for you!

## Independent Practice

25 minutes

Who can tell me what they did to problem solve today? Did anyone notice a pattern? For example, I'm listening for students to share that they noticed for squares they could multiply the value of one by the number of sides, that opposite sides of a rectangle are equal length, all sides of a square are equal. (MP7)

Now that you’re ready to go, I want you to put your brains to work. You have the freedom to create shapes and designs, as big or as small as you want, but you have to label each unit and find the perimeter for each one you draw! Get creative, because I know that you might find some great tricks for solving perimeter.

## Share Out

5 minutes

I want to hear from you guys what types of perimeter problems you created! Remember when you show us your figure, I also want to see how you labeled and solved to find the perimeter!