CK-12 Foundation
Ck 12: Geometry: Radius or Diameter of a Circle Given Area
[Free Registration/Login may be required to access all resource tools.] Find the radius or diameter of a circle given its area.
Texas Instruments
Texas Instruments: Circles: Circumference and Area
The idea of perimeter can be applied not only to polygons but to circles as well. The same idea can be said for the area of a circle. (Continued. See "before the activity.") [Requires Adobe Reader.]
Math2
Math2: Circles
This site has many useful formulas and examples relating to circles, including related definitions, circumference of a circle, area of a circle, length of a circular arc, area of a circular sector, equation of a circle in cartesian...
Houghton Mifflin Harcourt
Holt, Rinehart and Winston: Homework Help Independent Practice: Circles
Get independent practice working with finding the circumference, area and radius of circles. Each incorrect response gets a text box explanation and another try. Correct responses are confirmed.
Mr. Martini's Classroom
Mr. Martini's Classroom: Circles Geometry Review
This resource provides two levels of multiple choice questions to review the parts of a circle as well as area and perimeter.
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.
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.
BBC
Bbc: Circumference and Area of a Circle
This is where you can pick up some valuable pointers on how to find the circumference and area of a circle. There is also information on how to find the perimeter and area of a semicircle. When you finish working your way through the...
McGraw Hill
Glencoe Mathematics: Online Study Tools: Circumference and Area of Circles
This site gives a short interactive quiz which allows students to self-assess their understanding of the concept of finding the circumference and area of circles.
Thinkport Education
Math by Design: Circumference and Area of a Circle [Pdf]
Students will discover how to estimate and measure the circumference and area of a circle.
Oswego City School District
Regents Exam Prep Center: Area of Polygons and Circles
A lesson focusing on the area of polygons and the circumference of circles. Engaging, interactive practice worksheet, lesson plan, and related classroom activity complete this lesson.
Texas Instruments
Texas Instruments: Circle Around
In this activity, students compute the circumference and area of circles. They understand that the ratio of the circumference to the diameter is a value called pi. [Requires Adobe Reader.]
Texas Instruments
Texas Instruments: Arc Length and Area of Sectors
This is an introduction to finding the arc length and area of sectors of circles. Students should have the formulas for Circumference and Area of circles.
Discovery Education
Discovery Education: Web Math: Find Out Things About Circles
This WebMath site will assist with finding the radius, diameter, circumference, and area of a circle.
Khan Academy
Khan Academy: Area and Circumference of Parts of Circles
In this exercise, students practice find the area and circumference, of parts of circles. Students receive immediate feedback and have the opportunity to get hints and try questions repeatedly.
CK-12 Foundation
Ck 12: Geometry: Area of a Circle
[Free Registration/Login may be required to access all resource tools.] In this lesson students calculate the area of circles and the area of sectors of circles by using given information and formulas. Students examine guided notes,...
Other
Nearpod: Circles: Area and Circumference
In this lesson on circles, 7th graders will learn how to find the area and circumference of circles, semicircles, and compound shapes using formulas.
Khan Academy
Khan Academy: Area and Circumference of Circles Challenge
Try these challenge problems involving area and circumference.
Khan Academy
Khan Academy: Problem Solving With Area and Circumference of Circles
In this exercise, students practice problem solving the area and circumference of circles. Students receive immediate feedback and have the opportunity to get hints and try questions repeatedly.
Khan Academy
Khan Academy: Circumference of a Circle
Practice finding the circumference of a circle.
Khan Academy
Khan Academy: Circumference of Parts of Circles
Practice finding circumference of parts of circles.
Khan Academy
Khan Academy: Area of Parts of Circles
Practice problems finding area of parts of circles.
Math Open Reference
Math Open Reference: Circumference (Perimeter) of a Circle
Learn about the circumference of a circle with this helpful reference tool. Provides a detailed definition, examples, and an interactive activity that enhances further explanation. Includes links to related topics.
Khan Academy
Khan Academy: Circumference and Rotations
Practice these problems with circumference and rotations.