Curated OER
Circumference and Area of Circles
In this circumference and area worksheet, students find each for a set of 12 given circles; either diameter or radius are given. A website reference for additional resources and answers are provided.
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
Circles
In this circles activity, 10th graders solve and complete 20 different problems related to various circles. First, they find the radius and diameter of a circle with a given circumference. Then, students determine the measure of each...
EngageNY
The Area of a Circle
Introduce learners to two methods to estimate the formula for the area of a circle. The first method uses a sector of a circle to form a rectangle, and the other uses grids to estimate the area. The problems in the 18th segment of a...
Willow Tree
Area of Common Geometric Figures
Scholars can use area formulas, but can they apply what they know about area? The lesson challenges learners to think logically while practicing finding area of shapes such as rectangles, circles, parallelograms, triangles, and other...
Inside Mathematics
Circles in Triangles
Challenge the class with inscribed circles in triangles. The assessment task requests class members use their knowledge of circles and right triangles to prove two triangles are congruent. They go on to utilize their knowledge of...
Curated OER
Skills Practice: Area of Circles
Two practice pages with 10 problems each show circles and give their radii. Learners calculate the area. Answers are provided.
Illustrative Mathematics
Coins in a Circular Pattern
What starts as a basic question of division and remainders quickly turns abstract in this question of related ratios and radii. The class works to surround a central coin with coins of the same and different values, then develops a...
Illustrative Mathematics
Right Triangles Inscribed in Circles II
So many times the characteristics of triangles are presented as a vocabulary-type of lesson, but in this activity they are key to unraveling a proof. A unique attack on proving that an inscribed angle that subtends a diameter must be a...
Illustrative Mathematics
Right Triangles Inscribed in Circles I
One of the basic properties of inscribed angles gets a triangle proof treatment in a short but detailed exercise. Leading directions take the learner through identifying characteristics of a circle and how they relate to angles and...
Curated OER
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...
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
Volume of Cylinders and Cones
Line drawings of a circle, a cylinder, and a cone at the top of the page contain the formulae for area and volume of each shape. Learners complete the missing information in a chart that lists diameter, radius, height, and area and...
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...
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...
Raytheon
Geometry: Circles
In this geometric circumference worksheet, 8th graders calculate the circumference of each of the 18 circles. The remaining pages of the worksheet include formulas and lesson ideas on finding the circumference of circles.
Curated OER
Volume of a Cylinder
Middle and high schoolers calculate the volume of cylinders. They measure the height, radius and diameter of cylinders. Following given formulas, students calculate the area and volume of the cylinder. They compare cylinders and predict...
Mrs. Burke's Math Page
Let Them Eat Pi
Looking for a fun and creative way to celebrate Pi Day? Then this is the resource for you. From a scavenger hunt and trivia contest to PowerPoint presentations and skills practice worksheets, this collection of materials is a...
Curated OER
Diameter, Radius and Area
Students calculate the diameter, radius and area of a circle. In this geometry lesson, students investigate the different ratios of a circle. They calculate the surface are of each circle.
Curated OER
Circle Problems - Radius, Diameter, Circumference and Area
In this online math instructional activity, students determine the radius, circumference, diameter and area of circles. This excellent resource allows the students to check their answers, and to get "hints" should they run into...
Curated OER
Find Radius/Diameter
In this geometry worksheet, students calculate the radius and the diameter of the five given circles. There is an answer key included.
EngageNY
The Most Famous Ratio of All
Pupils develop a definition of a circle based upon its radius in the 17th segment of a 28-part series. They determine the relationship between the radius and the diameter of a circle. To round out the lesson, they use the formula for the...
Curated OER
Circumferences, Diameters, and Radii
Students explore circumferences, diameters, and radii. In this math lesson plan, students measure circumferences in inches and compute radii and diameters, given different circumferences.
Curated OER
Circles and Pi
Learners identify the relationship between the radius and Pi. In this geometry lesson, students calculate the circumference and area of a circle. They create visuals to help them see how the circumference relates to Pi.