EngageNY
Solve for Unknown Angles—Angles and Lines at a Point
How do you solve for an unknown angle? In this sixth installment of a 36-part series, young mathematicians use concepts learned in middle school geometry to set up and solve linear equations to find angle measures.
EngageNY
Copy and Bisect an Angle
More constructions! In this third installment of a 36-part series, learners watch a YouTube video on creating door trim to see how to bisect an angle. They then investigate how to copy an angle by ordering a given list of steps.
EngageNY
Similarity and the Angle Bisector Theorem
Identifying and verifying reproducible patterns in mathematics is an essential skill. Mathematicians identify the relationship of sides when an angle is bisected in a triangle. Once the pupils determine the relationship, they prove it to...
Curated OER
Supplementary, Complementary, and Vertical Angles
By using circles that they cut out and label themselves, learners literally "get a grip" on the angles they identify: supplementary, complementary, and vertical. They solve missing measurements based on properties of supplementary,...
Curated OER
Angles That Pair
Students identify angles. In this angles that pair lesson, students identify adjacent, vertical, complementary, and supplementary angles. They use straws, pretzel sticks to demonstrate given types of angles.
EngageNY
Solve for Unknown Angles—Angles in a Triangle
Assist your class with each angle of geometry as they use exterior angles to form linear pairs with adjacent interior angles. They cover multiple vocabulary terms and work practice problems, complete with justifications, before...
Curated OER
Geometric Angles
Students explore angles and their use in Geometry. Students investigate three different kinds of angles: obtuse, acute, and right angles through an online activity. They identify pairs of angles with special relationships: vertical,...
Curated OER
Exploring Angle/Pair Relationships
Students find missing angles and sides of triangles. In this geometry lesson plan, students create intersecting lines to measure angles. They use Cabri Software to create virtual angles.
Virginia Department of Education
Special Right Triangles and Right Triangle Trigonometry
Right triangles are so special! Use special right triangles to discover the trigonometric ratios. Pairs construct special right triangles and find the values of the ratios of the sides. In the process, they discover the ratios stay the...
Curated OER
Sum of Exterior Angles of Polygons
Have fun calculating angles for different polygons. The class differentiate the relationship between the interior and exterior angles of polygons. They discuss linear pair as it related the polygons and their angles. This is done as they...
Alabama Learning Exchange
"I Saw the Sine"
Discover trigonometric ratios that complement each other. Using two videos, the lesson introduces the trigonometric ratios. The class discovers the relationship between the sine and cosine of complementary angles.
Curated OER
Geometry for the Technologies
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...
Curated OER
Angles Lesson Plan
Students explore the relationship of angles as it relates to 2 and 3-D shapes. In this geometry lesson, students differentiate between acute, obtuse, right, alternate interior, exterior and adjacent angles. They manipulate a math...
Curated OER
Triangle Exterior Angles Theorem
Students identify the measure of missing exterior angles. In this geometry lesson,students define and apply the exterior angle theorem to solve problems. They use Cabri software to create different angles and make investigations.
Curated OER
Exploring Angle Pair Relationships
Students 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.
Curated OER
Angle Pairs
High schoolers practice identifying right, vertical, and adjacent angles using a Smartboard. They then determine measurements of all of the angles when only one measurement is given.
Curated OER
Exploring Characteristics Needed to Prove Two Trianlges Congruent
Tenth graders explore congruent triangles. In this geometry lesson, 10th graders investigate the conditions necessary to prove two triangles congruent. The lesson combines dry erase board activities and the use of technology.
EngageNY
Incredibly Useful Ratios
Start the exploration of trigonometry off right! Pupils build on their understanding of similarity in this lesson that introduces the three trigonometric ratios. They first learn to identify opposite and adjacent...
EngageNY
Applying Tangents
What does geometry have to do with depression? It's an angle of course! Learners apply the tangent ratio to problem solving questions by finding missing lengths. Problems include angles of elevation and angles of depression. Pupils make...
Curated OER
Angles Lesson Plan
Learners stud angles, and then play the "What's Your Angle?" game. They complete at least 10 computer generated problems from the Angles Applet.
Curated OER
Angle Measurement of Aircraft Wings and Tails
Students measure the angles of wings and tails of various aircraft using a protractor. They estimate and check their measurements. They investigate aircraft being developed and tested at NASA Dryden.
Curated OER
Angles and Arcs
Pupils discuss the sum of central angles and use string to create them on circles. They find the measure and length of both minor and major arcs.
Students give examples of concentric, similar, and congruent circles and congruent arcs.
Curated OER
Quadrilateral Clues
Fourth and fifth graders work in pairs explore quadrilaterals. In this problem-solving lesson, learners participate in hands-on activities that require them to identify, describe, compare, and classify quadrilaterals. This is meant...
Curated OER
Geo-Critters (Geometry Critters)
Students read the book The Math Curse by Jon Scieszka and study geometry. In this geometry lesson, students identify geometric shapes and their properties. Students create a geo-critter.