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Overview
3rd Grade Math
Geometry and Measurement
28. TX.3.7.B
28.1 Perimeter: Grid squares and polygons
Perimeter: Mastering Grid Squares and Polygons
Unlock the secrets of perimeter calculations using grid squares and polygons. Learn essential formulas, tackle real-world problems, and boost your geometry skills with our comprehensive guide.
What You'll Learn
Identify perimeter as the total distance around the outside of a 2D shape
Calculate perimeter by adding all side lengths of a polygon together
Count outside edges only when finding perimeter of grid square figures
Apply rectangular perimeter formulas: 2×length + 2×width or 2×(length + width)
Recognize that different shapes can have the same perimeter
What You'll Practice
1
Counting grid square edges to find perimeter of irregular shapes
2
Adding all sides to calculate perimeter of polygons like pentagons and hexagons
3
Using formulas to find perimeter of rectangles with given dimensions
4
Drawing different rectangles with the same perimeter
5
Solving for unknown side lengths when perimeter is given
Why This Matters
Understanding perimeter helps you measure real-world boundaries like fencing a garden, wrapping a gift, or calculating the distance around any space. This foundational measurement skill connects to area, construction, and everyday problem-solving in math and beyond.
This Unit Includes
18 Video lessons
Practice exercises
Learning resources
Skills
Perimeter
Grid Squares
Polygons
Rectangles
Measurement
Length and Width
Problem Solving
TX Curriculum Aligned