Teachers' Domain
Introduction to Angle Measure
An all-encompassing package provides video clips that demonstrate real-world activities that have to do with angles. After watching the Cyberchase cartoons, learners discuss why a "v" shape is used to measure a turn. A pair of vital...
Utah Education Network (UEN)
The Angle Tangle
Fourth and fifth graders identify three types of angles, recognize that angles are measured in degrees, measure angles using protractors or angle rulers. They classify angles as a class, classify angles on pattern blocks, and complete a...
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...
Curated OER
Lesson 3: Measuring Angles
Young scholars use a protractor to measure angles. They classify angles by type: right angle, acute angles, and obtuse angles. Students build and draw right, acute, and obtuse angles. They discuss how do people in various professions use...
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...
Curated OER
Angles
Fourth and fifth graders investigate angles and name them according to the criteria for obtuse, acute, and right angles. They examine a human-made yarn pattern on the floor of their classroom and identify angles, vertices, and types of...
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.
Curated OER
Does Your Field Measure Up
Students measure angles using a plane table kit. In this geometry lesson, students use trigonometric identities to find the values of the length of a football field.
Curated OER
Basic Geometry ... A Pathway to Angles
Help 9th graders identify lines, points, rays, and planes in geometry. They practice identifying, measuring, and drawing angles of different degrees. This is a fundamental lesson to help students learn the building blocks of geometry.
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...
Curated OER
Geometry Challenge
Students explore angle relationships and measure angles with a protractor by hand and online. They explore various websites and complete online activities and complete a worksheet.
Curated OER
Geometry of Triangles Using a Protractor
Seventh graders use a protractor to measure angles and solve a problem involving distance. In this measuring angles with a protractor lesson plan, 7th graders calculate the distance of a line on a diagram by using a protractor to measure...
Curated OER
An Introduction to Angles
Students identify and create angles. In this angle measurement lesson, students use sticks to make models of angles, then measure and name each angle.
Curated OER
Measure: Bearings and Scale Drawings
Pupils practice drawing geometric figures. In this geometry lesson, learners complete an activity that requires them to draw angles and shapes to the nearest degree.
EngageNY
Inscribed Angle Theorem and Its Applications
Inscribed angles are central to the lesson. Young mathematicians build upon concepts learned in the previous lesson and formalize the Inscribed Angle Theorem relating inscribed and central angles. The lesson then guides learners to prove...
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...
Curated OER
Measuring the Earth
Students use principles of geometry to measure the circumference of the Earth. In this applied geometry lesson, students use mathematics to determine scientific information. They make measurements, calculate the central angle, and use...
Curated OER
What is my Angle? App
Learners estimate angle measures in this this estimating angle measures lesson. They use an application on their graphing calculator that shows various settings involving angles and then they estimate the angle measure of a clock's...
Virginia Department of Education
Angles, Arcs, and Segments in Circles
Investigate relationships between angles, arcs, and segments in circles. Pupils use geometry software to discover the relationships between angles, arcs, and segments associated with circles. Class members use similar triangles to...
Curated OER
Acute Triangles
Learners study acute triangles. They measure angles using a protractor, then classify the triangles as either right, obtuse, or acute. Everyone creates a design for a Navajo rug using only acute triangles.
Curated OER
Sample Lesson Plan on Lines and Angles
Student complete worksheet using the definitions of lines and angle vocabulary. They define the word and follow a direction given on the worksheet such "construct a line." They complete an online tutorial on how to measure angles using a...
Curated OER
Measuring Angles
Middle schoolers explore angle measure as they estimate angle measure and measure and draw angles of less than 360 degrees. The instructional activity emphasizes the use of estimation when measuring angles.