Same Area, Different Perimeter

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Content Area(s):  
Grade Level(s):  
Oregon Common Core State Standards: 
Lesson Plan Details
2-3 class periods
Students will compare different rectangles with the same area to discover the change in perimeter.
Promethean board, enVision Math curriculum-Topic 14, iPads, Pages Application with grid paper created with a table, Pre & Post assessment created with Active Inspire software, Student Survey created with Active Inspire Software, and Active Inspire clickers.

This lesson is the eighth lesson in our curriculum’s unit on Area and Perimeter.  In the previous lessons we have worked to understand area, looked at the area of squares and rectangles, looked at the area of irregular shapes, parallelograms, and triangles, worked with perimeter, and now are investigating the same area, but different perimeters.  In addition to this area and perimeter unit we have worked with multiplication and factors, which should aid in the understanding of same area, different perimeters.  Finally, the use of our iPads and Pages application is a prerequisite since all of our technology is new to our school this year.


In this lesson students will come to the Promethean Board and calculate the area and perimeter for multiple rectangles with contrasting perimeters, but identical areas.  We will consider the connections between the factors of a number that represents a rectangles area and measure of the perimeters.

Pre-assessment: using an Active inspire flipchart and clickers.

Then students will use their iPads to create different rectangles with varying perimeters, but identical areas.  This will be done in the Pages Application using a grid table I have created in preparation of the lesson and emailed to each student.

After they have created these rectangles on their own iPads, they will take turns coming to the Promethean Board and creating all of the possible rectangles there as well.

Post assessment: using the Active inspire flipchart and clickers.

Students will answer survey questions from the Active inspire flipchart using the Pages Application and email their completed survey to me.



I gave the students a five question pre-assessment and an identical post assessment to measure the improvement in concept performance.  In addition, I gave the students a three-question survey at the end of the lesson.  The survey asked the following questions: Do you understand the relationship between area and perimeter better now then before the lesson?  Did using technology help give you a better understanding of this concept?  What questions do you still have about area and perimeter?

The class performance on the pre-assessment was a mean of 54%, while the post assessment showed a 28% improvement with a mean score of 82%.

Looking at the survey, 15 of 17 students feel they understand the concepts better now then before the lesson.  My second question asked students if they felt the technology help them with conceptual understanding and 14 of 17 students felt the technology did help with understanding.  I only had three questions from students and unfortunately all three questions were unrelated to the lesson.

Oregon Educational Technology Standards
Creativity and Innovation: 
1A. Apply existing knowledge to forecast possibilities and generate new ideas, products or processes.
Communication and Collaboration: 
2A. Interact and collaborate with peers, experts, or others employing a variety of digital environments and media.
Technology Operations and Concepts: 
6B. Transfer current knowledge to learning of new technologies.