Math Open Reference
Math Open Reference: Secant
Learn about secants with this handy reference guide. Provides a detailed definition and an interactive activity that enhances further explanation. Includes links to related topics.
Math Open Reference
Math Open Reference: Congruent
Learn about congruent with this handy reference guide. Provides a detailed definition and examples that enhance further explanation. Includes links to related topics.
Khan Academy
Khan Academy: Graph a Circle From Its Expanded Equation
Given the expanded equation of a circle, graph the circle.
Khan Academy
Khan Academy: Graph a Circle From Its Standard Equation
Given the standard form equation of a circle, graph the circle.
Khan Academy
Khan Academy: Graph a Circle From Its Features
Given information about the center and radius of a circle, graph it.
Khan Academy
Khan Academy: Points Inside/outside/on a Circle
Given the center and radius of a circle, determine if a point is inside of the circle, on the circle, or outside of the circle.
Math Open Reference
Math Open Reference: Arc
Learn about arcs with this handy reference guide. Provides a detailed definition, examples, and an interactive activity that enhances further explanation. Includes links to related topics.
Math Open Reference
Math Open Reference: Angle Measure of an Arc
Learn about the angle measure of an arc with this handy reference tool. Provides a detailed definition, examples, and an interactive activity that enhances further explanation. Includes links to related topics.
CK-12 Foundation
Ck 12: Interactive Geometry: 10.2 Equations of Circles
Derive the equation of a circle with the help of the Pythagorean Theorem.
Khan Academy
Khan Academy: Radians & Arc Length
Solve problems related to radians and arc length like finding an arc length given the central angle and radius.
CK-12 Foundation
Ck 12: Interactive Geometry: 1.8 Circles
Understand circles and their measurement applications.
Quia
Ixl Learning: Pi
Brush up on your math skills relating to pi then try some practice problems to test your understanding.
PBS
Pbs Learning Media: Square Wheeled Tricycle: Radius and Circumference
This interactive exercise focuses on working with the radius of various circles to find the circumference and area as well as challenging you to find the distance a square wheel travels around the track.
PBS
Pbs Learning Media: Math + Arts: Circle Designs
In this activity, students explore circumference and diameter by creating an abstract design with circles. Media resources and teacher materials are included.
Khan Academy
Khan Academy: Praxis Core Math: Circles Lesson
A basic review of circles and how to calculate the circumference, radius, diameter, and area. Includes practice questions.
Purple Math
Purplemath: Sectors, Areas, and Arcs
Explains formulas for areas of sectors of circles and lengths of arcs. Demonstrates how to use the formulas in each of degrees and radians.
E-learning for Kids
E Learning for Kids: Math: Market Place: 2 D Shapes and Patterns
On this interactive site, students learn to identify squares, circles, and triangles.
Other
Nearpod: Circles & Pi
In this lesson, 7th graders will learn vocabulary associated with circles and use formulas to find the area and circumference of circles.
E-learning for Kids
E Learning for Kids: Math: World of Fish: Geometry
Students will play an interactive game to identify the circumference, radius, center, and diameter of circles.
Government of Alberta
Learn Alberta: Mathematics Glossary: Circle
Get a visual and animated definition of the term "circle" from LearnAlberta.ca's Mathematics Glossary, as well as examples of circles in the real world.
Math2
Math2.org: Expansions for Pi
A listing of some of the more famous formulas developed and used throughout the centuries for defining pi are given and explained.
National Council of Teachers of Mathematics
The Math Forum: Conic Sections/circles
This site provides a catalog of Web sites and Web pages that deal with circles.
Wolfram Research
Wolfram Math World: Circles
This site provides definitions for a wide range of topics dealing with circles.
National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Degrees in a Circle
Dr. Math answers a students question as to why a circle contains 360 degrees.