Illuminations
Circumference and Areas of Circles
Middle and high schoolers listen to a scenario about a puppy and use the scenario to develop formulas in order to find the area of a circle. In this circumference lesson, pupils understand how to find the radius, diameter, area of a...
National Research Center for Career and Technical Education
Transportation, Distribution, and Logistics: Tire and Wheel Assemblies
Is bigger really better? By the end of this lesson, learners will be able to apply formulas for computing the diameter of tires and wheel assemblies. Begin by showing a slide presentation that will review definitions for radius and...
Curated OER
Circumference, Diameter, Radius
Sixth graders will determine the circumference, diameter, and radius of a circle. In this circle lesson plan, 6th graders will measure the appropriate amount to find these measurements on circles.
Curated OER
Covering and Surrounding
Students develop techniques for estimating the area of a circle and use ideas about area and perimeter to solve practical problems. For this area and perimeter lesson, students apply the concepts of perimeter and area to the solution of...
Curated OER
Circle Circus
Third graders find the radius and diameter of a bubble. In this radius and diameter lesson, 3rd graders create bubbles on their desk and find the radius and diameter of the bubble. Students work in partners to define circle terms and...
Curated OER
Exploring Diameter and Circumference
Learn how to identify the diameter and circumference of a circle. Then, collect data on a circle and relate it to the diameter and circumference of a circle. Last, plot data and find the line of best fit.
EngageNY
Rectangles Inscribed in Circles
Putting a rectangular object into a circular one—didn't the astronauts on Apollo 13 have to do something like this? Learners first construct the center of a circle using perpendiculars. They then discover how to inscribe a rectangle in a...
Mathematics Assessment Project
Inscribing and Circumscribing Right Triangles
High schoolers attempt an assessment task requiring them to find the radii of inscribed and circumscribed circles of a right triangle with given dimensions. They then evaluate provided sample responses to consider how to improve...
EngageNY
Arc Length and Areas of Sectors
How do you find arc lengths and areas of sectors of circles? Young mathematicians investigate the relationship between the radius, central angle, and length of intercepted arc. They then learn how to determine the area of sectors of...
Curated OER
Measuring the Area of a Circle
When mathematical errors happen, part of the learning is to figure out how it affects the rest of your calculations. The activity has your mathematicians solving for the area of a circular pipe and taking into consideration any errors...
Curated OER
Finding the Circumference and Area of a Circle
Sixth graders discover what circumference is. In this measurement lesson, 6th graders identify the radius and diameter of different circles. Students discover how to find the area of a circle using the radius and diameter.
Curated OER
The Circle's Measure
Students explore circumference and diameter. In this math lesson plan, students apply their knowledge of circumference and diameter to solve mathematical riddles. Students apply this knowledge to find circumference and diameter of...
Curated OER
Equations of Circles
Young scholars will define circle and radius. In this radius lesson, students are given a circumference, they will write an equation and sketch the circle. Young scholars will match graphs of circles to their equations.
Curated OER
Tangent Properties
Students explore properties of tangent lines. In this properties of tangent lines lesson, students discuss the perpendicular relationship between a tangent line on a circle and the circle's radius. Students use that...
Curated OER
Circumference and Area of a Circle
Students investigate the area and circumference of a circle. In this geometry lesson, students estimate and measure the radius, diameter and circumference of a circle. This assignment has an online part that is interactive.
Curated OER
Parts of a Circle
Sixth graders use yarn, paper plate, and other materials to identify parts of a circle. In this parts of a circle lesson plan, 6th graders identify the circumference, radius, diameter, and other parts of a circle.
Curated OER
Square Circles
Students analyze and demonstrate how a circle can be measured in square units and examine how diameter, circumference and radius are related.
Curated OER
Pi as a Ratio
Eighth graders measure the circumference and the diameter of circular objects and record the measured values of the circumference and the diameter in a table. They then record their measurements in centimeters and use their data to...
Curated OER
Math and Circumference
Sixth graders explore geometry by utilizing mathematical formulas. In this circumference lesson, 6th graders identify the difference between diameter, circumference and radius in a circle. Students review the formulas for finding...
Curated OER
A Slice of Pi
Math pupils, by viewing a video, discover the history of pi and some of the applications of its uses in the world today. They conduct an experiment by measuring the diameter and circumference of various circular objects to calculate...
Curated OER
Crop Circles
Students calculate the area and circumference of a circle. In this geometry lesson, students solve word problems with circles and create formulas to calculate the area. They find the rate and complex area of a circle.
Virginia Department of Education
Circles in the Coordinate Plane
Make the connection between the distance formula and the equation of a circle. The teacher presents a lesson on how to use the distance formula to derive the equation of the circle. Pupils transform circles on the coordinate plane and...
Illustrative Mathematics
Seven Circles III
A basic set-up leads to a surprisingly complex analysis in this variation on the question of surrounding a central circle with a ring of touching circles. Useful for putting trigonometric functions in a physical context, as well as...
Curated OER
Circles
Tenth graders explore and define the radius and diameter of a circle. In this geometry lesson, 10th graders calculate the circumference and area of a circle using real world objects and shapes. They discuss chords and lines tangent...