Georgia 3.GSR.8.1
The Standard
Determine the perimeter of a polygon and explain that the perimeter represents the distance around a polygon. Solve problems involving perimeters of polygons.
Georgia's K-12 Mathematics Standards · Determine the perimeter of a polygon presented in real-life, mathematical problems.
Teacher's field guide
What This Standard Means
What Students Need to Do
- Students find the total distance around a polygon by adding all side lengths. They solve story problems and explain what the total means in context.
What Mastery Looks Like
- Students correctly add every side length, including repeated or missing lengths they must determine. They label the answer with units and explain it as the length of the boundary.
Common Misconceptions
- Students may count squares instead of measuring side lengths, or add only the labeled sides. Some confuse perimeter with area or forget the unit of measure.
How to Assess It
- Give students a rectangle with sides 7 cm and 4 cm. Ask them to find the perimeter and explain what their answer measures.
Lesson moves
Ways to Teach It
Give pairs craft sticks and rulers to build polygons, measure each side, and record the total boundary length.
Ask students to explain in writing why a 3-by-5 rectangle has a perimeter of 16 units, not 15 square units.
Play Perimeter Match by having students pair polygon cards with measurement cards showing the correct total side length.
Measure a bulletin board or tabletop, then calculate how much border trim or tape would go all the way around it.
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Printable 3.GSR.8.1 Worksheet
A ready-to-print activity worksheet aligned to 3.GSR.8.1, with an answer key for the teacher on its own page. No account needed.
PDF, US Letter, prints cleanly in black and white.
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Related Standards
- 4.GSR.8
Identify and draw geometric objects, classify polygons based on properties, and solve problems involving area and perimeter of rectangular figures.
- 3.GSR.6.1
Identify perpendicular line segments, parallel line segments, and right angles, identify these in polygons, and solve problems involving parallel line segments,...
- 3.GSR.8
Determine the perimeter of a polygon presented in real-life, mathematical problems.
- 3.GSR.6
Identify the attributes of polygons, including parallel segments, perpendicular segments, right angles, and symmetry.
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