Lesson Plan
Curated OER

Patterns in the Sums of Polygon Angles

For Teachers 6th
Sixth graders discover the patterns of sums of polygon angles. In this math lesson, 6th graders study the properties of geometric shapes to solve problems as they participate in hands-on activities.
Lesson Plan
Curated OER

The Sum of All Angles

For Teachers 7th - 10th
Learners add up the different angles using the angle addition postulate. In this geometry lesson plan, students differentiate between interior and exterior angles. They calculate the different angles for triangles and use proof to show...
Worksheet
Curated OER

Angles

For Students 6th - 8th
In this math learning exercise, students measure a series of angles. Then they measure the angles in the triangles and determine the sum of the angles.
Interactive
Curated OER

Interior Angles of Polygons

For Students 9th - 12th
In this online math worksheet, students determine the interior angles of polygons given their exterior measurements. This excellent resource allows the students to check their answers, and to get "hints" should they run into...
Lesson Plan
Curated OER

Study Buddies: Classifying Triangles

For Teachers 4th - 5th
In this math worksheet, students analyze an informative chart about the measurement and angles of equilateral, isosceles and scalene triangles. Students then answer 5 questions about classifying triangles.
Unit Plan
Mathematics Vision Project

Geometric Figures

For Teachers 10th - 12th Standards
Logical thinking is at the forefront of this jam-packed lesson, with young mathematicians not only investigating geometric concepts but also how they "know what they know". Through each activity and worksheet, learners wrestle with...
Worksheet
Curated OER

Classify and Measure Angles #1

For Students 2nd - 3rd
In this angles worksheet, students classify and measure 2 simple angles. Worksheet is part of a site with additional activities and links.
Worksheet
Curated OER

Polygons - Sum of Interior Angles

For Students 7th - 8th
For this polygon worksheet, learners determine the sum of the interior angles of a figure. Given the sum of the interior angles, they determine the number of sides of a polygon and the measure of one central angle. This one-page...
Organizer
Curated OER

Triangle Angle-Sum Theorem

For Students 5th - 8th
In this polygons instructional activity, students fill out a graphic organizer about the name of the polygon, the number of sides, the angle sums, and more. Students complete this for 5 polygons.
Interactive
Curated OER

Try These Angles! Exploring Angles: Post Test

For Students 5th - 8th
In this angles worksheet, students answer multiple choice questions about angles on their own and angles inside shapes. Students complete 10 multiple choice questions.
Worksheet
Curated OER

Forty Mental Math Angle Problems

For Students 10th - 11th
For this angle worksheet, students answer forty mental math questions divided into four problem sets.  These problems require students to remember angle facts and so simple calculations mentally.
Interactive
Curated OER

Try These Angles! Exploring Angles

For Students 5th - 8th
In this angles activity, students answer multiple choice questions about different types of angles in shapes. Students complete 10 questions.
Lesson Plan
Curated OER

Exterior and Interior Angles of Triangles

For Teachers 10th
Tenth graders explore the exterior and interior angles of triangles. They use a theorem in order to prove a theorem about all polygons. Students use the theorem and its applications to find the angles of different types of triangles.
Lesson Plan
Curated OER

Angles and Parallel Lines

For Teachers 6th
Sixth graders draw parallel and intersecting lines to observe and examine the characteristics of alternate interior angles, vertical angles, corresponding angles, and supplementary angles. Through observation, they discover the...
Worksheet
Curated OER

Polygons

For Students 10th
In this polygons worksheet, 10th graders identify and define both a polygon and a convex polygon and then, they apply two theorems that involve the interior and exterior angles of a convex polygon. First, they find the sum of the...
Worksheet
Curated OER

Polygons

For Students 10th
In this polygons worksheet, 10th graders solve 18 various types of problems related to different forms of polygons. First, they state the number of sides for each convex polygon and then, use the polygon shown to respond to each of 6...
Worksheet
Curated OER

Exploring Similar Polygons

For Students 10th
In this exploring similar polygons worksheet, 10th graders solve 9 various types of problems related to determining whether each polygon is similar or not. First, they write 3 equal ratios to show corresponding sides are proportional to...
Lesson Plan
EngageNY

Similar Triangles in Circle-Secant (or Circle-Secant-Tangent) Diagrams

For Teachers 9th - 12th Standards
First angle measures, now segment lengths. High schoolers first measure segments formed by secants that intersect interior to a circle, secants that intersect exterior to a circle, and a secant and a tangent that intersect exterior to a...
Lesson Plan
Curated OER

Interior Angles of Regular Polygons

For Teachers 9th - 12th Standards
Students investigate the interior angles of a triangle. In this geometry lesson, students create the formula to calculate the angles inside a triangle. They observe the total sum of a triangles angle on the navigator.
Lesson Plan
Curated OER

Betweenness and the Sum of Parts

For Teachers 9th - 12th Standards
High schoolers differentiate lines and angles using betweenness in this geometry lesson. They differentiate angles and lines using Cabri Jr. and analyze the data and make conjecture.
Interactive
Curated OER

Angles in a Triangle

For Students 10th
For this geometry worksheet, 10th graders determine the measure or measures of the missing angle(s) in a triangle. The one page interactive worksheet contains four questions. Answers and hints are included. 
Worksheet
Lone Star College

Geometry Worksheet II

For Students 7th - 10th Standards
Young geometers get practice with the algebra of angles in an extensive skills practice worksheet. Supplementary, complementary, and vertical angle relationships are used, along with parallel lines cut by a transversal and angle sum...
Worksheet
Curated OER

Shapes and Designs

For Students 10th
For this shapes and designs worksheet, 10th graders solve and complete 6 different types of problems. First, they fill in the first two columns of the table show with their shapes. Then, students measure the interior angles of each...
Lesson Plan
Curated OER

Exploring Characteristics of Triangles

For Teachers 9th - 11th
Students draw triangles and explore the classification of each using the measures of interior angles and lengths of sides. They investigate the sum of the interior angles of various triangles and conjecture and prove the theorem: The...