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.
CK-12 Foundation
Ck 12: Geometry: Segments From Secants
[Free Registration/Login may be required to access all resource tools.] This concept teaches students to solve for missing segments from secants intersecting circles.
CK-12 Foundation
Ck 12: Elem Math: Classify Objects as Rectangles, Squares, Circles, or Triangles
[Free Registration/Login may be required to access all resource tools.] Students practice classifying various two dimensional shapes as rectangles, squares, circles or triangles.
CK-12 Foundation
Ck 12: Elem Math: Classify Objects as Rectangles, Squares, Circles, or Triangles
[Free Registration/Login may be required to access all resource tools.] Students watch a video and attempt practice problems on classifying rectangles, squares, circles and triangles.
CK-12 Foundation
Ck 12: Elem Math: Identifying Rectangles Squares Circles and Triangles
[Free Registration/Login may be required to access all resource tools.] Students watch a video overview and attempt practice problems on identifying rectangles, squares, circles and triangles.
CK-12 Foundation
Ck 12: Geometry: Diameter or Radius of a Circle Given Circumference
[Free Registration/Login may be required to access all resource tools.] In this lesson students find the diameter or radius of a circle given its circumference. Students examine guided notes, review guided practice, watch instructional...
Annenberg Foundation
Annenberg Learner: Geometry: Circles: Inscribed Angles
Study inscribed angles in semicircles and quarter-circles. What conjectures can you make about the measure of an inscribed angle in semi- or quarter-circles?
BBC
Bbc: Bitesize Review Circle Introduction
Do you need to learn about Pi, circumference, or the area of a circle or just have a quick refresher about them? This British web site will take you through the basics and offers a quick on-line test to help you check your understanding.
Oswego City School District
Regents Exam Prep Center: Arcs in Circles
Provided are definitions of arcs in circles, an example and theorems to assist with test preparation.
Texas Instruments
Texas Instruments: Conics: Circles
In this study of conics, students will examine the derivation of equations for circles. There are two general equations for circles. The first is a circle whose center is at the origin, while the second is a circle whose center is not at...
McGraw Hill
Glencoe Mathematics: Online Study Tool: Self Check Quiz on Circles
The online assessment exhibits knowledge of advanced mathematical concepts in Trigonometry. The questions evaluate students on the topic of circles.
CK-12 Foundation
Ck 12: Segments From Chords
[Free Registration/Login Required] Students will move points to create a midpoint on a chord. Click 'Challenge Me' to answer a practice question.
Paul Dawkins
Paul's Online Notes: Algebra: Graphing and Functions
Students investigate functions and graphing. Topics examined are lines, circles, graphing functions, inverse functions, and combining functions. Class notes, definitions, and examples with detailed solutions are included. The class notes...
Oswego City School District
Regents Exam Prep Center: Area of Polygons and Circles
How would you find the area of a polygon or circle? Explore this concept with engaging activities at this test prep site. Here you will find detailed problem solving strategies with accompanying visuals, a reference table with formulas,...
National Council of Teachers of Mathematics
The Math Forum: Analytic Geometry: Polar Coordinates
This site from The Math Forum provides great information on polar coordinates. You can access this information either by clicking on the coordinates link or just scrolling down, it is the first one listed on the page. Includes several...
Analyze Math
Analyze Math: Inscribed and Central Angles in Circles
The geometry tutorial investigates the definitions and theorems related to inscribed and central angles in circles. An example with a detailed solution is included.
Johan Claeys
Math Abundance: The Circle: Basic Concepts
Goes over the equation of a circle, parametric equations of a circle, intersection of circle and line, tangent line in a point of a circle, etc.
Purple Math
Purplemath: Completing the Square: Circle Equations
This tutorial works through two examples step by step that shows how to complete the square for finding the center and radius of a circle.
Walter Fendt
Walter Fendt: Apps on Mathematics
Apps for Arithmetic, Plane Geometry, and other Geometry concepts are provided.
University of Cambridge
University of Cambridge: Maths and Sports: Olympic Rings
This activity explores shapes and circles by encouraging children to look really hard at something they will see very often in the run-up to London 2012, and is designed to be accessible to primary pupils at Key Stage 1.
Khan Academy
Khan Academy: Angles in Circles
Practice measuring angles using a circle protractor, solve problems about angles as part of a circle. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Illustrative Mathematics
Illustrative Mathematics: G Co Seven Circles Ii
In this task, seven pennies are placed in a circle so that they are all touching one in the center and their neighbors. Students are asked to find as many rigid motions of the plane as they can which are symmetries of this configuration...
Illustrative Mathematics
Illustrative Mathematics: G Co, G Srt Seven Circles I
In this task, seven pennies are placed in a circle so that they are all touching one in the center and their neighbors. The question is whether this will work with other equally-sized circles. Aligns with G-SRT.C and G-CO.C.10.
Illustrative Mathematics
Illustrative Mathematics: G Gpe Slopes and Circles
The purpose of this task is to lead students through an algebraic approach to a well-known result from classical geometry, namely, that a point X is on the circle of diameter AB whenever angle AXB is a right angle. This consists of...