CK-12 Foundation
Ck 12: Geometry: Pi
[Free Registration/Login may be required to access all resource tools.] Identify pi as the ratio of a circle's diameter to a circle's circumference.
Math Open Reference
Math Open Reference: Pi
Learn about Pi with this helpful reference tool. Provides a detailed definition and examples that enhance further explanation. Includes links to related topics.
National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Irrational Pi
Math Forum response to the question of why pi is not rational if it is a ratio of circumference to diameter.
CK-12 Foundation
Ck 12: Pi
[Free Registration/Login Required] Students will determine Pi by exploring the points on a circle. Click challenge me to answer practice questions and click learn more to watch a video.
Alabama Learning Exchange
Alex: A Piece of Pi
This lesson uses graphing to help students understand that pi is a constant and is the slope of the line graphed on a circumference vs. diameter graph.This lesson plan was created as a result of the Girls Engaged in Math and Science...
Science and Mathematics Initiative for Learning Enhancement (SMILE)
Smile: Diameter,circumference,radius & the Discovery of Pi
This site provides a good project for students to use to explore the circumference of a circle.
OER Commons
Oer Commons: Measuring Circles
Seventh graders will measure the circumference and diameter of round things in the classroom and discover the ratio pi. They will see that the ratio of a circle's circumference to its diameter can be used to solve for the circumference...
PBS
Pbs Learning Media: Math + Arts: Circle Designs
In this lesson, young scholars explore circumference and diameter by creating an abstract design with circles. Media resources and teacher materials are included.
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.]
Better Lesson
Better Lesson: Exploring Circumference
What is pi, anyway? Students explore the relationship between circumference and diameter by measuring a variety of circles and use it to derive the formula for circumference.
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 find the area of a circle given its radius or diameter. Students examine guided notes, review guided practice, watch instructional videos and...
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 find the area of a circle given the radius or the diameter. Students examine guided notes, review guided practice, watch instructional videos...
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 find the area of a circle given the radius or the diameter. Students examine guided notes, review guided practice, watch instructional videos...
CK-12 Foundation
Ck 12: Geometry: Circle Circumference
[Free Registration/Login may be required to access all resource tools.] In this lesson students find the circumference of a circle given the radius or the diameter. Students examine guided notes, review guided practice, watch...
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.
ClassFlow
Class Flow: Area of a Circle
[Free Registration/Login Required] This flipchart reviews basic geometric forms in nature and real objects. Students are then given opportunities to find the area of circle and parts of a circle, given the radius and/or diameter of the...
PBS
The Math of Bicycles: Wheel Figure This Out (Grades 4 7)
Several good activities here. Look particularly at Wheel Figure It Out (which is the opening page) and Gearing Up. There are answers to the very good questions at the bottom of each.
Cuemath
Cuemath: Area of a Circle
This mini-lesson explores the area of a circle. Provides a definition, examples, and practice questions with answers.
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.
Ducksters
Ducksters: Kids Math: Circle Geometry
Circle Geometry math for kids contains information for students to learn about terms radius, diameter, circumference, chord, and pi.
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...
Other
Ic Teachers: Shapes, Circles (Basic)
This basic website will give you lots of information about circles. There are also some questions to test your circle knowledge.
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,...
CK-12 Foundation
Ck 12: Geometry: Circumference
[Free Registration/Login may be required to access all resource tools.] In this lesson students calculate a circle's circumference. Students examine guided notes, review guided practice, watch instructional videos and attempt practice...