I love area and perimeter. There are so many hands-on applications that help students understand the importance of knowing these skills, and I am able to incorporate a ton of movement into my lessons. Plus if I am really on my game, I can teach these skills with linear measurement and maximize my instructional efficiency…and who doesn’t love that idea these days? However, I find that many of my students struggle to differentiate area from perimeter, often confusing the two. Today I am going to share a little trick to help your students differentiate the two.
|Image Credit: fotosviajeras | Dollar Photo Club|
So here are a few tricks.
- CREATE A VISUAL: As we work through the lesson, we record the word perimeter in our journals. However, we capitalize and bold the RIM to remind them the peRIMeter is the measurement of the outside “rim” of the shape. They also draw a rectangle in their journals, and write the word perimeter going all the way around the outside…over and over again for my friends with small penmanship. We also write AREA in our journals, and I let them color in the inside of the As and R to remind them the area is the inside. Then they go back to that rectangle they drew and write AREA as big as they can fit on the inside.
- COMPUTE THEM DIFFERENTLY: Many of my kids realize that if all the sides are the same length they can multiply the length by the number of sides to get the perimeter. However, for my struggling learners, I encourage them to always add with perimeter and always multiply with area until they get the hang them. This really helps them distinguish the two because they are using different operations to solve.
- USE COLOR: Finally, if they are given a visual, I have them outline shapes they are finding the perimeter for and color in shapes when they are asked for the area. We use colored pencils to make it easy to see our work (and prevent the mess of markers).
I also work hard to give my students TONS of activities and opportunities to practice both skills together and separately because the research supports that increased opportunities means increased learning as long as I give meaningful feedback. Here are a few of the resources that have helped me teach area and perimeter to my students:
This set has students sort cards into groups of four so students can practice matching the visual of the labeled shape diagram with the measurements for area and perimeter. There are a total of 8 sets to create…or to differentiate for your struggling students, just give them 4 sets (16 cards) rather than the 8 (32 cards). I am also planning to use this in small group. My kiddos still struggling with the topic will review one set with me as a mini-lesson, and I will give them the next set to do in partners to assess their growth.
Just be sure to cut the cards in advance and keep a copy of the sheets for an answer key!
Depending on my group of students I either use these as a whole class review/formative assessment or as a station, while I am meeting with small groups of students who are struggling. The set contains both customary (standard) and metric unit measurements for 48 total task cards. Plus I built in some word problems to give my students a chance to see the type of story problem they may see on standardized state assessments.
What tips or tricks do you have for teaching students to distinguish area from perimeter? Leave them in the comments below.