Math Mammoth
Measuring Angles
The first of two pages displays various angles as the measure of degrees of a circular arc. An explanation is written, and learners are asked to model each by holding up two pencils as the rays. The second page provides instruction on...
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...
Illustrative Mathematics
Finding an Unknown Angle
Teach your class how to apply their knowledge of geometry as they explore the unknown. In order to find an unknown angle, students must understand that rectangles have four interior right angles, that right angles have 90 degrees, and...
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 resource covers a wide range of...
CK-12 Foundation
Radian Measure: Unit Circle Conversions
Individuals investigate the relationship between radian and angle measurements by using an interactive to find the angle measurement for given radian measures. Users answer questions to convert between the two measurements.
CK-12 Foundation
Angle Pairs: Angle Measurements
As one changes, so does the other. Scholars use an interactive to see how changes in the measure of one angle of a complementary or supplementary pair of angles affect the measure of the other angle. They answer a set of challenge...
CK-12 Foundation
Measuring Rotation: Aircraft Headings
Measure angles in more than one way. The interactive introduces the concept of measuring angles from 0 to 360 degrees. Scholars explore the relationships between the angle and reference angles along with coterminal angles.
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 plan to investigate angles created by secant lines that intersect at a point exterior to the circle....
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.
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 newfound...
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 intersecting lines,...
West Contra Costa Unified School District
Arcs and Angles
Noah didn't construct this kind of arc. High school scholars first explore how angles can be formed in circles. They then learn relationships between angles and arcs by conducting an exploratory activity where they position and draw arcs...
CK-12 Foundation
Supplementary Angles: Spiderweb Angles
The itsy, bitsy spider went up the virtual wall. An interactive allows users to change the angles in a spider web. They must attend to supplementary angles as they answer challenge questions throughout the interactive.
K-5 Math Teaching Resources
Angles Template
Young mathematicians learn to see geometry from different angles with this simple printable resource. Providing multiple visual examples of angles, this simple document can be used as an instructional tool, a skills practice exercise, or...
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
Angles of Rotation in Standards Positions: Clock Angles
Use a clock face to develop angles representing standard position angles. The interactive allows pupils to create angles using the hands of a clock. Scholars discover that there is a difference in the angle formed using a clock face and...
CK-12 Foundation
Trigonometric Functions of Negative Angles
When is the trigonometric value of a negative angle the same as the positive angle? Pupils compare the values of trigonometric functions for different angles and their negatives. The interactive resource provides a visual display to make...
El Paso Community College
Geometry Definitions
Geometry is full of shapes, figures, and corresponding things here and there. The guide shares all of the key pieces of geometric information in a nicely color-coded and labeled sheet.
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...
CK-12 Foundation
Conversions between Degrees and Radians: Charting Hours in the Day
Forget hours, divide the day into radians instead. Class members convert the angles in a pie chart of daily activities into radian measures. They add angle measures for multiple activities then determine a relationship between the radian...