Curated OER
Pitch Perimeters
Teach your class how to calculate the perimeter of a rectangle with this handy visual aid. Perimeter is described and calculated. Next, students are shown a rectangle and asked to determine the perimeter and discuss their strategies....
Shodor Education Foundation
Shodor Interactivate: Lesson: Perimeter (Elementary)
In this lesson students will practice finding the perimeter of regular and irregular shapes with right angles and the appropriate units for measuring perimeter.