The purpose of this activity is for students to understand that many different shapes can have the same perimeter. Students start to focus more specifically on shapes with repeated side lengths, so they can leverage the efficient addition strategies elicited in the Warm-up (MP7).

• “How did you find the perimeter of this shape?”
• “What other strategies could you use so you wouldn’t have to count one unit at a time?”

• Invite students to share a variety of methods for finding the perimeter of the different shapes. Ask students who found the perimeter of shapes in efficient ways to share their reasoning.
• Consider asking: “Did anyone find the perimeter in a different way?”
• “Shapes A and G look very different but have the same length for their perimeter. How could that be?” (The shapes may look different but the distance around each is the same number of units. Different shapes can have the same perimeter.)

The purpose of this activity is for students to draw shapes with specific perimeters. Students may create any shape that uses horizontal and vertical lines. Since diagonal lines that connect the dots are not one length unit, students cannot find the perimeter of shapes that include diagonal sides. Encourage students to be creative in drawing their shapes to reinforce the idea that different shapes can have the same perimeter.

• Select previously identified students to share their strategies for drawing shapes for one of the perimeters in the first problem.
• “What perimeter did you and your partner choose to draw a shape for? Why did you pick that number?”