Scholastic
Study Jams! Measure Angles
Get a quick review on measuring angles with this step-by-step guide using a protractor. Watch the correct way to measure angles and finish with an assessment on correct techniques to measure special angles.
EngageNY
The Angle Measure of an Arc
How do you find the measure of an arc? Learners first review relationships between central and inscribed angles. They then investigate the relationship between these angles and their intercepted arcs to extend the Inscribed Angle Theorem...
CK-12 Foundation
Angle Measurement: Fuel Gauge Angles
Once you start looking, angles appear everywhere in our daily lives. A creative lesson has learners use the angles created by a fuel gauge to practice the Angle Addition Postulate. They see how changing the angle parts does not...
Virginia Department of Education
Classifying Angles
Don't be obtuse, this geometry unit is the just the right resource for educating the acute young minds in your class. From classifying and measuring angles, to determining the congruence of shapes, this...
Curated OER
Triangle's Interior Angles
Given a pair of parallel lines and a triangle in between, geometers prove that the sum of the interior angles is 180 degrees. This quick quest can be used as a pop quiz or exit ticket for your geometry class.
EngageNY
Secant Angle Theorem, Exterior Case
It doesn't matter whether secant lines intersect inside or outside the circle, right? Scholars extend concepts from the previous lesson to investigate angles created by secant lines that intersect at a point exterior to the circle....
CK-12 Foundation
Angle Measurement: Adding Angles
Build angles from angles. Using the Angle Addition Postulate, learners find the measures of unknown angles. The interactive simulation shows a visual representation of the postulate and allows individuals to manipulate the angles and...
EngageNY
Solve for Unknown Angles—Angles and Lines at a Point
How do you solve for an unknown angle? For 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.
Scholastic
Study Jams! Construct Angles
Practice those protracting skills while watching the step-by-step guide on the correct way to use this angle measuring tool. The resource follows with assessment questions testing their ability to understand and use the protractor...
EngageNY
The Inscribed Angle Alternate – A Tangent Angle
You know the Inscribed Angle Theorem and you know about tangent lines; now let's consider them together! Learners first explore angle measures when one of the rays of the angle is a tangent to a circle. They then apply their...
McGraw Hill
Lines and Angles
Why was the obtuse angle upset? Because it was never right! A valuable resource is loaded with background information on types of angles and lines. Learners review the characteristics of parallel, perpendicular, and...
Lane Community College
Review Sheets: Geometry
Full of problems with polygons, angles, lines, and triangles, your learners get a multi-page packet that provides all they need to know. It contains many of the standard problem types as well as some more challenging questions.
CK-12 Foundation
Angle Classification: Angle Exploration
Acute or obtuse? Seems right to me! As scholars explore the simulation, they investigate angle measures. Questions ask them to classify the angles using correct naming conventions.
EngageNY
Angle Sum of a Triangle
Prove the Angle Sum Theorem of a triangle using parallel line and transversal angle relationships. Pupils create a triangle from parallel lines and transversals. They find angle measures to show that the angles of a triangle must total...
Mathematics Vision Project
Circles: A Geometric Perspective
Circles are the foundation of many geometric concepts and extensions - a point that is thoroughly driven home in this extensive unit. Fundamental properties of circles are investigated (including sector area, angle measure, and...
EngageNY
Sine and Cosine of Complementary Angles and Special Angles
Building trigonometric basics here will last a mathematical lifetime. Learners expand on the previous lesson in a 36-part series by examining relationships between the sine and cosine of complementary angles. They also review the...
EngageNY
Congruence Criteria for Triangles—AAS and HL
How can you prove it? Guide classes through an exploration of two possible triangle congruence criteria: AAS and HL. Learners connect this criteria to those previous learned and also explore criteria that does not work. The lesson...
CK-12 Foundation
Angle Classification: Crazy Quilt
There's more to a quilt than just a pretty pattern—there's geometry! Explore angle classification using an artistic approach to show your class that quilt designs are really just intricate geometric patterns. Here, scholars create a...
EngageNY
How Do Dilations Map Angles?
The key to understanding is making connections. Scholars explore angle dilations using properties of parallel lines. At completion, pupils prove that angles of a dilation preserve their original measure.
101 Questions
Pool Bounce
Use geometry to improve your pool game! Learners analyze the front half of a pool shot to determine its resulting path. By measuring the angle of incidence, they are able to predict the path of the ball.
EngageNY
Solve for Unknown Angles—Transversals
Lead your class on an exciting journey through the world of math as they review geometry facts and solve for unknown angles. They learn how to use auxiliary lines and congruent angles to correctly complete each practice problem...
EngageNY
Unknown Angles
How do you solve an equation like trigonometry? Learners apply their understanding of trigonometric ratios to find unknown angles in right triangles. They learn the meaning of arcsine, arccosine, and arctangent. Problems include...
CK-12 Foundation
Angles: The Angle of Discovery
Practice important angle vocabulary using an interactive lesson. As learners manipulate vertical angles, they watch the supplementary and congruent angles adjust. Questions pertaining to vocabulary and measurements follow their exploration.
CK-12 Foundation
Angle Classification: Angles in the Game of Pool
Make a game of angle classification. Using the direction of the pool ball, scholars determine the measure of the created angles. They work to create and classify different types of angles throughout an engaging interactive.