SWBAT apply their understanding of measurement to find the perimeter of objects in our classroom

Perimeter is all around us!

5 minutes

*Yesterday we started to think about perimeter, and today we’re going to have some fun with it! I have this problem on the board and I’m hoping you guys will be able to help me solve it. I need to make sure I’m going to have enough fence! Please turn to your elbow partner and talk about whether or not you think I'm going to have enough fence for my yard. Make sure we are using our partner talk rules for conversation (I think this because..... I disagree because..... I agree because.... How did you.....)*

A great tool for ensuring students are using appropriate language and sentence starters for partner talk is to post them on sentence strips in the classroom and then continue to model using them and referring to them.

35 minutes

*Have you noticed that when we're working together, we keep discovering that math is all around us. Today, when I was getting ready, I noticed that perimeter was all around me. I saw that my paper had a perimeter, our rug on the floor has a perimeter, perimeter was everywhere! Take a moment to look around the room to see if there are some things that you notice have perimeter. *

We spend some time discussing what we notice around us and what helps us see that those things have perimeter. (MP2) When students offer their suggestions, if I sense some uncertainty I ask the students to run their hand or fingers along the perimeter of the object they - or a peer - suggested.

*Today, will get to locate items in our classroom and find the perimeter of each one. You need to record the the name of the object, the length of each side and what unit of measurement you used. Both rulers and nonstandard measurement tools, like markers, pencils and even you can be used today! *

Students will work in partners to measure various objects around the classroom. I want students to feel safe to be creative with what they choose, as well as to see what objects might be more reasonable choices. (MP5)

5 minutes

*Wow, that was fun! I even had some of you measure me in pencils and with rulers! Who can share with us something they worked on with their partner?*

I allow a few groups to share so that we can spend some time talking about what tools they used and why they chose their particular tools. (MP3)