Instructional Video17:08
2
2
Flipped Math

Measuring Angles

For Students 9th - 12th Standards
An informative presentation shows pupils how to name and measure angles. Scholars revisit the different types of angles and their definitions and use their knowledge of what an angle bisector is to solve algebraic problems. At the end,...
Worksheet
K12 Reader

Kinds of Angles

For Students 2nd - 3rd Standards
Have you ever wondered how circles and angles relate to each other? Read a passage about right angles, acute angles, and obtuse angles, and answer reading comprehension questions about the information you learn. 
Instructional Video2:06
Corbett Maths

Angle Bisector

For Students 8th - 11th Standards
Cut it in half with a compass and straightedge! Using construction tools, a video shows how to create an angle bisector. The presenter points out what it means to bisect an angle in terms of the measure and distances from the sides of...
Instructional Video0:53
Corbett Maths

Angles in the Same Segment – Proof

For Students 8th - 12th Standards
If angles intercept the same arc, the angles must be the same size. The quick video talks through the proof of showing the reason two inscribed angles that intersect the same arc have the same measurement. Pupils then create their own...
Assessment
Inside Mathematics

Hopewell Geometry

For Teachers 9th - 12th Standards
The Hopewell people of the central Ohio Valley used right triangles in the construction of earthworks. Pupils use the Pythagorean Theorem to determine missing dimensions of right triangles used by the Hopewell people. The assessment task...
Lesson Plan
EngageNY

Solving for Unknown Angles Using Equations II

For Teachers 7th Standards
The third activity in the series of 29 asks learners to identify types of angles to verify angle relationships. They find unknown measures using vertical, adjacent, complementary, supplementary, and 360-degree angles.
Activity
Big Kid Science

Measuring Shadows Using an Ancient Method

For Teachers 8th - 12th
How did ancient peoples determine the height of really tall objects? Young scientists and mathematicians explore the concept of using shadows to measure height in a hands-on experiment. Paired pupils measure shadows, then calculate the...
Interactive
CK-12 Foundation

Angle-Side-Angle Triangles: Caution Tape

For Students 10th - 12th Standards
Don't lose your marbles. Scholars use an interactive to create a triangle that closes off a portion of a sidewalk with loose marbles. The Law of Sines helps them find the side measures of such a triangle.
Lesson Plan
Curated OER

Measuring Angles in a Quadrilateral

For Teachers 9th - 12th Standards
High schoolers explore quadrilaterals in this geometry lesson. They will draw a quadrilateral, measure the angles, and find the sum of the measures of the interior angles using Cabri Jr. The interactive capabilities of Cabri Jr. allow...
Lesson Plan
EngageNY

Solve for Unknown Angles—Angles in a Triangle

For Teachers 9th - 10th Standards
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...
Worksheet
Kuta Software

Polygons and Angles

For Students 6th - 10th
Get out those protractors! Geometers measure interior and exterior angles of 10 polygons, including a 24-gon. They also calculate the interior angle sum of the polygons. 
Lesson Plan
EngageNY

Inscribed Angle Theorem and Its Applications

For Teachers 9th - 10th Standards
Inscribed angles are central to the instructional activity. Young mathematicians build upon concepts learned in the previous instructional activity and formalize the Inscribed Angle Theorem relating inscribed and central angles. The...
Lesson Plan
EngageNY

Sine and Cosine of Complementary Angles and Special Angles

For Students 9th - 10th Standards
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...
Lesson Plan
Virginia Department of Education

Angles, Arcs, and Segments in Circles

For Teachers 9th - 11th Standards
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...
Activity
Noyce Foundation

What's Your Angle?

For Students K - 12th Standards
Math can be a work of art! Reach your artistic pupils as they explore angle measures. A creative set of five problems of varying levels has young learners study interior and exterior angle measures of polygons. The introductory levels...
Lesson Plan
EngageNY

Using Trigonometry to Find Side Lengths of an Acute Triangle

For Students 9th - 10th Standards
Not all triangles are right! Pupils learn to tackle non-right triangles using the Law of Sines and Law of Cosines. After using the two laws, they then apply them to word problems. 
Interactive
Scholastic

Study Jams! Classify Angles

For Students 4th - 8th Standards
What a great introduction to the world of angles. See the different types of angles and their corresponding degree measurements. Use the provided assessment to test understanding with a variety of questions. 
Lesson Plan
Project Maths

Introduction to Angles

For Teachers 6th - 8th Standards
Approach the lesson from the right angle. A discussion-based lesson leads helps learners understand angles in terms of rotation. Individuals use manipulatives to explore the properties of angles and learn how to name them. The lesson is...
Lesson Plan
EngageNY

Applying the Laws of Sines and Cosines

For Students 9th - 10th Standards
Breaking the law in math doesn't get you jail time, but it does get you a wrong answer! After developing the Law of Sines and Cosines in lesson 33 of 36, the resource asks learners to apply the laws to different situations. Pupils must...
Lesson Plan
Virginia Department of Education

Arc Length and Area of a Sector

For Teachers 9th - 11th Standards
What do skateboarding and baked goods have in common with math? You can use them to connect half-pipe ramps and cakes to arcs and sectors. Pupils compare the lengths of three different ramp options of a skate park. They calculate the...
Lesson Plan
Curated OER

Identifying Angles

For Teachers 4th - 5th
Students identify names of angles. They use a large clock to demonstrate angles using certain times of day. Given a geoboard, students create figures with acute, right, and obtuse angles.
Worksheet
Curated OER

Classifying and Measuring Angles

For Students 5th
In this classifying and measuring angles worksheet, 5th graders use a protractor to measure 9 angles and write what kind of angle it is.
Worksheet
Curated OER

Arcs and Central Angles

For Students 10th
In this arcs and central angles worksheet, 10th graders solve and complete 25 different types of problems. First, they use the letters shown in the diagram to name each portion. Then, students find the measure of each arc or angle named....
Lesson Plan
Curated OER

Measurement: The Size is Right

For Teachers Pre-K - 8th
Specific learning goals are grouped for different grade levels spanning pre-kindergarten to eighth grade. After preparing the questions and materials, you call a learner to come in front of the class and play the game. Young learners...