A polygon is a closed plane figure composed of at least three line segments that do not cross.None of the sides are curved. Perimeter is a measure of the distance around a polygon and is found by adding the measures of the sides. Area is the number of iterations of a two-dimensional unit needed to cover a surface.The two-dimensional unit is usually a square, but it could also be another shape such as a rectangle or an equilateral triangle.
- Opportunities to explore the concepts of perimeter and area should involve hands-on experiences (e.g., placing tiles (units) around a polygon and counting the number of tiles to determine its perimeter and filling or covering a polygon with cubes (square units) and counting the cubes to determine its area).
| **All students should**
Understand the meaning of a polygon as a closed figure with at least three sides.None of the sides are curved and there are no intersecting lines. Understand that perimeter is a measure of the distance around a polygon. Understand how to determine the perimeter by counting the number of units around a polygon. Understand that area is a measure of square units needed to cover a surface. Understand how to determine the area by counting the number of square units.
| **The student will use problem solving, mathematical communication, mathematical reasoning, connections, and representations to**
·Measure each side of a variety of polygons and add the measures of the sides to determine the perimeter of each polygon. ·Determine the area of a given surface by estimating and then counting the number of square units needed to cover the surface. |