Curated OER
Easy Worksheet: Right Triangles and Circles
In this right triangles and circles worksheet, students solve 4 short answer problems. Students describe a right triangle formed by point on a circle and an angle measure.
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...
K12 Reader
Kinds of Angles
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.
K12 Reader
What’s Your Angle?
Start out with angles by asking your pupils to read this reading passage. Class members will learn about degrees, right angles, acute angles, and obtuse angles and then respond to five questions about the text.
EngageNY
Secant Lines; Secant Lines That Meet Inside a Circle
Young mathematicians identify different cases of intersecting secant lines. They then investigate the case where secant lines meet inside a circle.
Illustrative Mathematics
Seven Circles III
A basic set-up leads to a surprisingly complex analysis in this variation on the question of surrounding a central circle with a ring of touching circles. Useful for putting trigonometric functions in a physical context, as well as...
Willow Tree
Circle Graphs
Pie isn't just for eating! Scholars learn to create pie charts and circle graphs to represent data. Given raw data, learners determine the percent of the whole for each category and then figure out the degree of the circle that percent...
EngageNY
Special Triangles and the Unit Circle
Calculate exact trigonometric values using the angles of special right triangles. Beginning with a review of the unit circle and trigonometric functions, class members use their knowledge of special right triangles to find the value of...
Project Maths
The Unit Circle
It's not just any circle—it's the unit circle. The fourth lesson in the series is an introduction to the famous unit circle. While working through a series of activities, young scholars learn the components of the unit circle and how to...
CK-12 Foundation
Unit Circle: Medieval Castle Defense
Who needs a plan — let trigonometry protect you! Pupils determine the angle of an approaching enemy to a village wall. The scholars determine the exact value of trigonometric functions for the angle. Class members use trigonometry to...
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...
Flipped Math
Unit 11 Review: Circles
Solve problems around a circle. Pupils watch a video that shows how to apply concepts about circles and related angles and segments to find solutions to word problems. Learners then review the different concepts from the unit in...
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...
NASA
Photons in the Radiative Zone: Which Way Is Out? An A-Maz-ing Model
Can you move like a photon? Young scholars use a maze to reproduce the straight line motion of a photon. The second in a six-part series of lessons on the sun has learners measure angle of incidence and refraction to determine the path...
Curated OER
Arcs in Circles
In this arcs in circles worksheet, 10th graders identify 10 different circles and the measurement of their arcs. First, they determine the length of a minor arc to the nearest integer. Then, students determine the radius of a circle...
Curated OER
Angles - Digger and the Gang
Students explore angle estimation and measurement. In this angle lesson, students define obtuse, acute, and right angles, and practice measuring angles using a protractor. Students participate in an online angle estimation activity.
CK-12 Foundation
Tangent Graphs: Slope and Angle
Learning about tangents doesn't have to be a slippery slope. Pupils drag a point around a unit circle to see how angle affects the slope of a line. They individually answer a set of challenge questions to come to the conclusion that...
Illustrative Mathematics
The Geometry of Letters
Use the alphabet as a tool for teaching your class about geometric figures. Break apart capital letters into line segments and arcs. Classify angles as right, acute, or obtuse. Identify parallel and perpendicular lines. An excellent...
Mr. Williams Maths
Eight Circle Theorems Page
Your learners will find these circle theorems nicely organized with diagrams included that present the geometric relationships between the circle circumference, chords, central and circumference angles and tangents.
Curated OER
Angles, Triangles, Quadrilaterals, Circles and Related
Students classify angles. In this angles lesson, students explore the characteristics of angles, triangles, quadrilaterals and circles. They identify polygons and sing a classifying angles song. Students participate in a manipulative...
Curated OER
Inscribed and Central Angles in a Circle
In this geometry worksheet, students find the missing angle that is inscribed inside of a circle. They define vocabularies related to the circle. There are 17 questions.
Curated OER
Opposite Angles in a Cyclic Quadrilateral
Learners investigate cyclic quadrilaterals in this geometry lesson. They use Cabri Jr to explore the sum of the measures of opposite angles in a cyclic quadrilateral. The dynamic nature of Cabri allows students to form and verify...
Curated OER
Quiz: Angles and Arcs in Circles - Central and Inscribed
In this angles and arcs in circles worksheet, students determine the angle and arc measurement in a circle from given information. This one-page worksheet contains ten problems.
Curated OER
Trig Cheat Sheet
Your pre-calculus learners will make use of this wonderful cheat sheet that summarizes all things trigonometric. Definitions based on both the unit circle and the right triangle are included, as well as many convenient trigonometric...