In this task, students create a rectangle with a given perimeter. They shade their own pattern and determine the area of negative space created by their pattern and the area of the positive space, the background area. Students explore these two spaces and connect that to the area being additive. This task can extend to a fraction of the area, percent of the area, and more. We’ve included a pattern for student exploration of different ways of seeing a symmetrical area pattern that can provide groupitizing practice.
The lesson plan and materials are provided in Google Slides— click below to view the slides or make your own copy of them. Slides labeled with a “T” in the upper right corner are included for teacher information about the lesson. Slides labeled with an “S” in the upper right corner are for students. If handouts are needed there are links to them in the teacher slides. All slides can be adapted.