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...
Curated OER
Algebra II - Lesson 10-3: Circles
In this equations of circles activity, students solve 4 short answer problems. Students find an equation of a circle given the center and radius.
Curated OER
Circles
A very basic presentation on the vocabulary associated with circles has come around. Math whizzes see definitions and examples of the radius, diameter, chord, and central angle of a circle. The last slide says "practice time," but there...
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
Making a Six-pointed Star
In this polygon worksheet, students identify and create a six-pointed star by completing 6 steps. First, they use a compass to trace a circle with a given radius. Then, students draw a point on circumference of the circle and place the...
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
Exploring Circles
In this exploring circles worksheet, 10th graders solve 10 different types of problems that are related to determining the different measures of a circle. First, they define a circle and its center. Then, students refer to the given...
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. In this area and perimeter lesson, students apply the concepts of perimeter and area to the solution of...
Mt. San Antonio Collage
Circles
Don't circle around the topic, but get right to the center with tons of practice regarding circles in geometry. The note-incorporated learning exercise provides guided practice through many topics such as central angles, inscribed...
Illustrative Mathematics
Tangent to a Circle From a Point
Learners see application of construction techniques in a short but sophisticated problem. Combining the properties of inscribed triangles with tangent lines and radii makes a nice bridge between units, a way of using information about...
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
Geometry: Calculating the Area of a Circle
For this area worksheet, students use the perimeter or radius to determine the area of a circle. This one-page worksheet contains 8 problems. This worksheet may be produced in printed form. Answers may be viewed on-line.
Curated OER
Geometry Review
In this geometry review worksheet, 10th graders solve and complete 33 different problems that include identifying various geometric figures and parts of a circle. First, they find the radius of each circle given its diameter. Then,...
Curated OER
Tangents, Secants, and Chords
In this tangents, secants and chords worksheet, 10th graders identify and solve 48 different problems that include using 3 different theorems for defining circles. First, they determine the area of each circle with C as the center and a...
Curated OER
Finding the Sum of the Perimeters of 3 Small Circles
For this geometry worksheet, students find the sum of the perimeters of three small circles. These small circles are tangent to each other and to a larger circle. The centers of the small circles have their centers on the diameter of...
Curated OER
Circles and Ellipses
In this circles and ellipses worksheet, students solve and complete 5 different types of problems. First, they write each equation in standard form. Then, students graph and label Write the equation of the ellipse whose center is the...
Curated OER
Circles and Ellipses
In this circles and ellipses worksheet, students solve and complete 12 different types of problems. First, they find the distance between the given pair of points. Then, students find the center and radius of each circle and sketch. They...
Curated OER
Tangents and Circles
For this tangents and circles worksheet, 10th graders solve 10 different problems that include various tangents and circles. First, they determine in each diagram whether the segments shown are tangents or not. Then, students determine...
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...
Concord Consortium
Bicycle Chain
Model a bicycle chain with circles and tangent lines. Given the dimensions of the sprocket wheels, young scholars calculate the length of the chain that surrounds them. A second task has learners write a function for the length of 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 their...
101 Questions
Rotonda West, FL
The shortest distance from point A to point B is a straight line—or is it? Young scholars determine the shortest route either along a circular path or through the center of the circle. Learners gain a unique perspective on arc length and...
Curated OER
Circles
In this circles worksheet, 10th graders solve and complete 16 various types of problems. First, they state the center and radius for the given equation and graph. Then, students determine if each point is on the circle, in its interior,...
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.