Curated OER
Circle Formulas
Tenth graders apply various circle formulas to determine radii, diameter, circumference, area, arc length, and sector area. The two page worksheet contains twenty-five problems. Answers are not provided.
Curated OER
Circumferences, Diameters, and Radii
Students explore circumferences, diameters, and radii. In this math lesson plan, students measure circumferences in inches and compute radii and diameters, given different circumferences.
Curated OER
Area of Sectors
In this area of sectors worksheet, students find the area of a given sector, area of inscribed figures, and area of shaded regions. This two-page worksheet contains 20 problems. An answer sheet is provided on the third page.
PBS
Pbs Learning Media: Finding the Circle's Center
In this video segment [3:10] from Cyberchase, the CyberSquad must find the exact center of a circle in order to save Motherboard.
Varsity Tutors
Varsity Tutors: Hotmath: Practice Problems: Circle Exercises
Twenty-five problems cover various circle activities. They are given with each step to the solution cleverly revealed one at a time. You can work each step of the problem then click the "View Solution" button to check each step of your...
PBS
Pbs Learning Media: Tricking Hacker
In this video segment from Cyberchase, the CyberSquad must reclaim the Totally Rad Ring by measuring its radius to create a perfect duplicate.
CK-12 Foundation
Ck 12: Area of Sectors and Segments: Pacman Area
[Free Registration/Login Required] Students are to determine the area of the shaded region between two radii. Click challenge me to answer practice questions and click learn more to watch a video.
Khan Academy
Khan Academy: Graph and Features of Ellipses
Find the center and radii of an ellipse from its graph, and vice versa. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
National Council of Teachers of Mathematics
The Math Forum: Multicultural Math Fair: Srinivasa's Spheres
Straightforward lesson that introduces learners to pi by letting them measure real objects and solve a challenge problem. Includes instructions and a "Data Sheet" for keeping track of measurements. Available in English and Spanish.