CK-12 Foundation
Regular and Irregular Polygons: Polygon States
Colorado would probably object if Wyoming enlarged its borders. Scholars use an interactive map to change the borders of U.S. states to see how angles change. They then answer questions about regular and irregular polygons.
Arizona Department of Education
Area and Perimeter of Regular and Irregular Polygons
Extend young mathematicians' understanding of area with a geometry lesson on trapezoids. Building on their prior knowledge of rectangles and triangles, students learn how to calculate the area of trapezoids and other...
Curated OER
Regular & Irregular Polygons
For this polygons worksheet, 7th graders identify and complete 8 different problems that include determining the types of various polygons. First, they use the table to the left to color each of the polygons illustrated. Then, students...
Curated OER
Countdown Challenge: Live Symmetry in Regular & Irregular Polygons
In this symmetry worksheet, students identify lines of symmetry in given polygons. They discover the correlation between the number of sides and the number of lines of symmetry. Students determine the lines of symmetry in irregular...
Curated OER
Jack and The Beanstalk Estimation
Introduce the day's lesson by reading Jack and The Beanstalk by Richard Walker, and then review the concept of area with your class. We don't always need rulers to measure, though! Teach learners how to use their hands to help us measure...
Illustrative Mathematics
Polygons
Identify shapes based on their attributes. Second graders are tasked to color triangles, quadrilaterals, pentagons, and hexagons specific colors. The one thing these shapes have in common? They are all polygons.
Buffalo State
A Five Day Approach to Using Technology and Manipulatives to Explore Area and Perimeter
Young mathematicians build an understanding of area and perimeter with their own two hands in a series of interactive geometry lessons. Through the use of different math manipulatives, children investigate the properties of...
Willow Tree
Interior Angles, Exterior Angles, and Diagonals of Polygons
How does the number of sides of a polygon affect the angle measures? Learners recognize a pattern in finding the total measure of interior and exterior angles and the number of diagonals. They use the patterns to calculate...
Alberta Learning
Area and Perimeter of Irregular Shapes
Evaluate young mathematicians' understanding of area and perimeter with this series of three assessment tasks. Challenging students to not only calculate the area and perimeter of irregular shapes, but to explain in writing their...
Curated OER
Perimeter All Around
Students explore perimeter and area of regular and irregular polygons. They experiment with color squares and create different arrangements using the same number squares. Then they compare the area and perimeter measurements of each.
Curated OER
Stained Glass Polygons
Pupils follow directions to make a stained glass window design of regular and irregular polygons with specific geometric elements. In this geometry lesson plan, students also analyze other classmate's designs.
Government of Hong Kong
Areas and Volumes - 2D Shapes
Unfortunately for young mathematicians, the world isn't made entirely of parallelograms, triangles, and trapezoids. After first learning the area formulas for these common shapes, students apply this new knowledge to...
Curated OER
Exploring Areas of Irregular Polygons
Students solve for the area of different polygons. In this geometry lesson, students identify and differentiate between regular and irregular polygons. They use properties of irregular polygons to solve problems.
Curated OER
Creature Design
Fifth graders create mathematical creatures. In this geometry lesson plan, 5th graders create a creature from regular and irregular geometric shapes. Students review vocabulary and construct an original creature based on a rubric.
Illustrative Mathematics
Regular Tessellations of the Plane
Bringing together the young artists and the young organizers in your class, this lesson takes that popular topic of tessellations and gives it algebraic roots. After covering a few basic properties and definitions, learners attack the...
National Security Agency
Awesome Area - Geometry and Measurement
Break out those math manipulatives, it's time to teach about area! Capturing the engagement of young mathematicians, this three-instructional activity series supports children with learning how to measure the area of squares,...
Curated OER
Introducing Angles
Sixth graders identify, compare and interpret the characteristics of polygons and angles in order to meet spatial sense, geometry and measurement standards. They also sort shapes into three categories, polygons (regular and irregular)...
Curated OER
Area and Perimeter
Learners find the area and perimeter of regular polygons and composite figures and examine the effect on the area and perimeter of a figure if the dimensions are multiplied by a constant. The nine page worksheet contains thirty-seven...
Curated OER
Perimeter of Polygons
Eighth graders discuss perimeter by relating it to the path they would take while walking their dog around a park. They find the perimeter of regular polygons and one irregular polygon. Students use graph paper to draw their own examples...
Curated OER
Area of Polygons
In this math worksheet, students find the area and perimeter of the regular and irregular polygons. They pay attention to use the proper measurements for calculation.
Virginia Department of Education 
Angles in Polygons
Polygons — it's all about the angles. Groups work with dynamic geometry software to find the sum of the measures of the angles of various polygons. After finding the information for several polygons, the groups generate a formula that...
Curated OER
Area of Irregular Polygons
In this geometry worksheet, 10th graders determine the area of irregular polygons.  The one page worksheet contains three problems.  Solutions are provided.
Curated OER
Powerful Polygons
Students scan the classroom to find different common shapes. They listen as the teacher defines polygon and regular polygon. The teacher demonstrates regular polygons via the Internet and the "Math is Fun" web site. Students go outside...
Houghton Mifflin Harcourt
Unit 6 Math Vocabulary Cards (Grade 5)
Acute angles, nets, and vertices are only a few terms that a set of flash cards includes. Among the 108 cards, two types are available; word cards printed in bold-faced lettering, and corresponding definition cards equipped with an...