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 instructional activity, pupils understand how to find the radius,...
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The Circumference of a Circle and the Area of the Region it Encloses
Bring your math class around with this task. Learners simply identify parts of a given circle, compute its radius, and estimate the circumference and area. It is a strong scaffolding exercise in preparation for applying the formulas for...
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Exploring Circles
Students explore circles using a graphing calculator. In this circles lesson, students write the equation of a circle with a given center and radius length. Students find the most appropriate model for each combination of data they...
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Area of Circles and Probability
Learners investigate the area of squares and circles. In this geometry lesson plan, students calculate the area and probability of simple events. They work on a laptop using Safari.
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Circles-Diameter, Circumference, Radius and the Discovery of Pi
Seventh graders measure the diameter, circumference and radius of a circle and find pi using the diameter and circumference. In this geometry lesson plan, 7th graders work in groups to find the diameter, radius, and circumference of...
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Area and Circumference of Circles
Learners view two PowerPoints and practice computing the area and circumference of circles. They must use given formulas to make their computations. The lesson includes links to both PowerPoints as well as a worksheet (with answer key).
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Geometry: Area, Scale Factor, Circumference
In this geometry worksheet, students solve 10 problems regarding area, scale factors, and circumference. Students, in 3 of the problems, are given the circumference and asked to work backwards to find missing information.
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Area and Circumference of Circles
Young scholars calculate the area and circumference of a circle as the lesson is presented through an animated Microsoft PowerPoint presentation. They then complete a project to review the previous day's material.
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Looking at Circumference
Middle schoolers understand where the number for pi comes from. They understand and use the formula for circumference. Students measure the circles given out and the diameters of those circles and record the results on their worksheet.
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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...
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The Area of a Circle
Eighth graders find the circumference and diameter of several lids, show the relationship of the two measurements and derive the formula for finding the area of a circle. In this area of a circle lesson plan, 8th graders find...
Mathematics Assessment Project
Calculating Arcs and Areas of Sectors of Circles
Going around in circles trying to find a resource on sectors of circles? Here is an activity where pupils first complete an assessment task to determine the areas and perimeters of sectors of circles. They then participate in an...
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Discovering Pi/Welcome to Pi Day
Students explore pi. In this circle measurement lesson plan, students define and identify radius, diameter, circumference, and perimeter. Students work in groups to measure several plastic lids and record their findings. Students compare...
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Equations of Circles
Students will define circle and radius. In this radius lesson,  students are given a circumference, they will write an equation and sketch the circle. Students will match graphs of circles to their equations. 
 
Virginia Department of Education 
Going the Distance
Estimate the value of one of the most famous irrational numbers. The hands-on instructional activity instructs classmates to measure the circumference and diameters of circles using yarn. The ratio of these quantities defines pi.
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
Small Angle Calculations
Students work with circles, angles and estimating angles in the night sky. In this circles and angles lesson, students practice measuring a degree using the circumference of a circle and apply the degree to determine a way to use their...
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Discovering Pi
Define terminology related to a circle. Practice accuracy in measuring and then create a spreadsheet based on data collected from solving for parts of a circle. Groups can have fun analyzing their data as it relates to Pi.
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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.
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Radius, Diameter and Circumference
In this circle worksheet, students use a drawing of a circle. The diameter is given. Students find the radius, circumference and area of the circle. On the second problem, students are shown a circle with a hole inside it. They compute...
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Circles
In this math worksheet, students solve 14 problems in which they calculate the diameter, radius, circumference and area of circles. There are no examples or formulas provided on this page; prior knowledge is assumed.
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The Circle's Measure
Students explore circumference and diameter. In this math lesson, students apply their knowledge of circumference and diameter to solve mathematical riddles. Students apply this knowledge to find circumference and diameter of various...
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Perimeter and Circumference
Learners consider perimeter and circumference. In this lesson plan on perimeter, students will determine relationships between perimeter and circumference using real life examples.
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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.