Students will have fun making circles out of chenille stems (pipe cleaners) and placing small circular pony beads while they practice drawing and identifying circles.

This mini-lesson explores the area of a circle. Provides a definition, examples, and practice questions with answers.

[Free Registration/Login may be required to access all resource tools.] This study guide reviews the terminology for circles (tangent, arcs, central angles) and the equation for a circle.

Derive the equation of a circle with the help of the Pythagorean Theorem.

Understand circles and their measurement applications.

Practice using your graphing calculator for geometry problems, including the use of the Pythagorean Theorem and the distance formula. If you get stumped or if you would like to check your work, then select the View Solution button, which...

This study guide on circles covers some vocabulary terms, and inscribed angles and polygons. It is available for download with free registration.

This lesson focuses on Euclidean Geometry terminology; such as line, point, line segment, congruence, circle, radius, ray, and more. It defines each term and provides an example of each.

When a line intersects a circle in exactly one point the line is said to be tangent to the circle or a tangent of the circle.

Learn about circle graphs or pie charts through examples and a video lesson.

Use this circle calculator to find the area, circumference, radius, or diameter of a circle. Given any one variable A, C, r or d of a circle you can calculate the other three unknowns.

Great resource to practice and strengthen math skills pertaining to Geometry. Math worksheets are printable, may be customized, and include answer keys.

In this instructional activity, students will estimate several dimensions of circles in everyday objects. Students will use the metric and customary systems for their estimations. This lesson plan was created by exemplary Alabama Math...

A java applet on this site illustrates the principles or spherical geometry.

[Free Registration/Login may be required to access all resource tools.] This concept teaches students four theorems about chords and how to apply them. Students examine guided notes, review guided practice, watch instructional videos and...

A collection of circular objects will be used to explore circumference and diameter of circles.

Understand the concept of diameter by learning the definition and symbols. Check-out the solved examples for better understanding and try your hand at solving a few interactive questions at the end of the page.

Kindergarteners love to identify shapes in their environment. In order effectively do that, they must be able to recognize different shapes by their specific attributes. In this lesson kindergartners learn about the attributes of a circle.

This site describes altitudes and orthocenters in triangles and their connections with the nine-point circle.

This lesson allows students to discover the number Pi. By measuring real life objects, students will get to see where the number Pi comes from as well as how the circumference formula is derived.This lesson plan was created as a result...

In this lesson learners will be engaged in an interactive online practice session using area and perimeter. Students will have to use critical thinking skills in order to unlock gates and learn more about the cups in the challenge.

Learn about the tangent definition in geometry, tangent geometry, tangent to a circle, tangent line equation. Check-out the solved examples for better understanding and try your hand at the tangent line calculator or solving a few...

[Free Registration/Login Required] Answer questions about the halves and fourths of circles and rectangles, and collect coins for each correct answer.

This CoolMath resource provides an introduction to some Precalculus formulas.