Lesson Plan
Curated OER

Polygons and Angles

For Teachers 6th
Sixth graders estimate the measurement of angles and then measure the exact distance using an angle ruler. In groups, they explore shapes and recognize the characteristics acute, obtuse and right angles. Students sketch required shapes,...
Lesson Plan
Curated OER

Circles and Angles

For Teachers 9th - 11th
Students identify tangents, chords and secants. In this geometry lesson, students graph circles and identify angles created by secant lines, tangent lines and chords.
Lesson Plan
Curated OER

Measurement of a Central Angle

For Teachers 9th - 11th
Students calculate the measurement of a central angle. In this geometry lesson, students identify properties of circles. They use Cabri software to create and analyze graphs.
Lesson Plan
Curated OER

Angle Action

For Teachers 5th - 7th
Students measure and label specified angles. In this angles lesson, students use a protractor to find angles that are acute, obtuse, and reflexive. Students then label each angle and match the angles the correct definition. This lesson...
Lesson Plan
Curated OER

Angles in Standard Positions

For Teachers 9th - 11th
Students identify positive and negative angles using the Unit Circle. In this pre-calculus lesson, students identify the different angles on a unit circle using the coordinate plane and the four different quadrants as a guide. They...
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...
Lesson Plan
Curated OER

Geometry for the Technologies

For Teachers 9th - 12th
Students discover how to use various tools to measure and draw angles. With protractors, they classify angles according to angle measure, identify vertical angles, and perform angle additions. For their final project, students create...
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.
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
Illustrative Mathematics

Regular Tessellations of the Plane

For Teachers 9th - 11th Standards
Bringing together the young artists and the young organizers in your class, this instructional activity takes that popular topic of tessellations and gives it algebraic roots. After covering a few basic properties and definitions,...
Lesson Plan
Willow Tree

Ratios and Proportions with Congruent and Similar Polygons

For Students 8th - 11th Standards
Investigate how similar and congruent figures compare. Learners understand congruent figures have congruent sides and angles, but similar figures only have congruent angles — their sides are proportional. After learning the...
Lesson Plan
Curated OER

Geometry w/o Figures - Week 7 (Basic Geometry Formulas)

For Teachers 10th - 12th
In this basic geometry worksheet, students use basic formulas of geometry to find the area of a polygons, the number of sides of a polygon, and sum of the angles of various polygons. This three-page worksheet contains eight problems.
Lesson Plan
Curated OER

Plain Figures and Measuring Figures

For Teachers 10th - 12th
Students investigate basic geometric concepts. In this geometry lesson, students explore solids through measuring and modeling. This assignment models the importance of understanding concrete objects in geometry.      
Lesson Plan
Curated OER

Transversal and Angles

For Teachers 10th
Tenth graders identify angles formed by parallel lines and a transversal. Using meter sticks and bolts, they perform hands-on activities to demonstrate the properties of parallel lines and congruent angles. They color code diagrams to...
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

For Teachers 5th
Fifth graders identify different angles according to its type that is determined according to taking a measurement of the degree. They also explore the vocabulary related to the concept.
Lesson Plan
West Contra Costa Unified School District

Investigating Similar Triangles

For Teachers 9th - 12th
Let your use of the resource be in proportion to its usefulness. Pupils investigate similar triangles by measuring side lengths and considering given angle measures. The results of the investigation help develop generalizations about...
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...
Lesson Plan
Curated OER

Exploring Angle Pair Relationships

For Teachers 9th - 11th
Learners investigate the relationship between angles of triangles. In this geometry lesson, students identify properties of right and non-right triangles. They differentiate between vertical and supplementary angles.
Lesson Plan
Curated OER

South Caro-angular

For Teachers 9th - 12th
Students classify and measure angles.  In this angular lesson, students measure, contruct, and classify angles.  They identify angles as acute, right, obtuse, and straight. 
Lesson Plan
Curated OER

Exploring Harmonic Conjugates

For Teachers 9th - 10th
High schoolers investigate harmonic conjugates using Cabri Software or the Ti Calculator to analyze harmonics. They explore different angles measurements as they move their circles around and solve problems.
Lesson Plan
Curated OER

Searching for Angles and Lines

For Teachers 6th - 8th
Middle schoolers work to find and reinforce concepts related to lines and angles. They identify the characteristics of shapes that have one, two, and three dimensions. The students also work on definitions related to the geometry of shapes.
Lesson Plan
Curated OER

Angle Measurement and the AD-1 Aircraft

For Teachers 7th - 8th
Students represent and solve problems using geometric models and apply geometric properties and relationships. They also practice constructing and measuring angles. By constructing, drawing, visualizing, and comparing geometric figures...
Lesson Plan
Curated OER

The Greedy Triangle-Intro to Geometric Shapes

For Teachers 4th - 6th Standards
 In this geometry lesson plan, learners read The Greedy Triangle and use geoboards to construct geometric shapes. They identify the number of sides and angles each shape has.