Free Printable Perimeter Worksheets for Class 3

In 3rd grade, students move beyond simply adding all side lengths. They learn to solve real-world perimeter problems, find an unknown side length given the perimeter and other sides, and critically, they learn to distinguish between the concepts of perimeter and area.

Use a concrete example. Take a rectangular piece of paper. Use a marker to trace the edge and explain, "This line around the outside is the perimeter." Then, color in the entire surface and say, "This colored space inside is the area." Having students build different rectangles with the same perimeter using tiles can also highlight the difference.

Practice should include a variety of problem types. Start with calculating the perimeter of polygons with all side lengths given. Then, introduce problems where students must find a missing side length of a rectangle when the perimeter is known. Finally, present word problems that require students to identify whether they need to find perimeter or area to solve.

The most significant misconception is confusing perimeter with area. Students will often multiply length and width when asked for perimeter. To assess this, give them a problem that provides both the perimeter and area of a shape and ask them to identify which is which, or provide a shape and ask for both measurements.

Wayground's worksheets are available in two convenient formats. You can print them as PDFs for focused, paper-and-pencil practice, or you can assign them as a digital quiz on the Wayground platform. Both formats cover the same problems and include a complete answer key for efficient grading.

Common Core standards for Grade 3 explicitly address perimeter. Students are expected to solve real-world and mathematical problems involving perimeters of polygons, including finding the perimeter given the side lengths and finding an unknown side length (CCSS.MATH.CONTENT.3.MD.D.8). This standard also requires them to exhibit understanding of the distinction between perimeter and area.

For students who confuse perimeter and area, provide visual aids that clearly label the "rim" for perimeter and the "inside" for area. On Wayground's digital worksheets, you can use the "Read Aloud" feature to help with word problems or "Reduced answer choices" to simplify calculations. For practice, start with worksheets that only ask for perimeter before introducing problems that mix both concepts.