Curated OER
Similar Triangles and Trapezoids, and Circles
High schoolers answer two problems involving area of shaded regions. Students then answers six questions involving perimeter, area, and circumferences. The remaining two questions involve ratios of similar figures.
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
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...
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...
Flipped Math
Sectors and Segments
It's a piece of pizza! Pupils learn about a sector of a circle as a slice of the circle and determine how to find its area. Scholars continue to find out how to calculate the segment of a circle based on the sector's area. At the end,...
Mathematics Assessment Project
Solving Problems with Circles and Triangles
After completing a task involving examining the ratio of areas of triangles and circles in a given figure, scholars examine sample responses to identify other strategies they could use to solve the problem.
Curated OER
Finding the Area of Polygons
Third graders are exposed to finding the area of polygons by decomposing figures and recomposing them into rectangles. This strategy allows children to expand on their prior knowledge of constructing shapes by rearranging parts into...
EngageNY
What Is Area?
What if I can no longer justify area by counting squares? Lead a class discussion to find the area of a rectangular region with irrational side lengths. The class continues on with the idea of lower approximations and...
Curated OER
Finding PI
Students select and use appropriate operations, methods and tools to compute or estimate using whole numbers. They develop and use formulas for determining the circumference and area of circles. Students determine and describe the...
101 Questions
Circle-Square
How do the area and perimeters of circles and squares compare? A clever video illustrates the change in the area of a circle and square while their total perimeter stays the same. The task is for learners to predict the point where the...
Flipped Math
Unit 9 Review: Area of Polygons
It's time to show what you know! Individuals first review finding the area of polygons using the formulas from parallelograms to regular polygons. They then brush up on finding the area and circumference of circles, as well as reviewing...
West Contra Costa Unified School District
Finding the Equation of a Circle
Tired of going around and around for a resource on circles? Scholars determine the general equation of a circle on a coordinate plane, then participate in an activity matching equations to the radii and centers of the circles...
Curated OER
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.
Curated OER
Circles and Arcs, Circumference and Area Multiple Choice
In this circles worksheet, students determine the circumference and area of circles. They compute the length of an arc and find the radius. This one-page worksheet contains 6 multiple-choice problems. This on-line...
Curated OER
Explorations for the Area Probability Applet
Math whizzes use the area probability applet to manipulate the size of the circle and the rectangle to explore the probability that a point in the rectangle is also in the circle.
Curated OER
Exploring Circles
Students explore circles using a graphing calculator. For 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...
Curated OER
A Practical Application For Area
First graders investigate the concept of surface area and find the coverage for the surfaces in a building that includes carpet or walls. The application of finding the area is practical using the everyday objects to help them to make...
Balanced Assessment
Star from Square
Quilting is not only beautiful and unique—it is a mathematical art. Show your classes how to design a quilting block while practicing area and circumference of circles. Scholars create a star from a square and then find the circumference...
Curated OER
Area of a Circle Worksheet
For this geometry worksheet, 6th graders identify the area of the four given circles by using the given diameters. There is a space for students to show their work.
Curated OER
Area and Circumference of Circles
Students calculate the area and circumference of a circle as the activity is presented through an animated Microsoft PowerPoint presentation. They then complete a project to review the previous day's material.
Curated OER
Finding Areas of Triangles, Rectangles, and Circles
Students find the areas of geometric shapes. In this geometry lesson students find and measure the sides, perimeters, and areas of quadrilaterals, triangles, and circles. Students relate the measures to the others by using formulas.
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
Looking at Circumference
Young scholars 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.
Curated OER
Mensuration: Area
In this area worksheet, pupils read story problems, draw diagrams, and find the area of described polygons. This eight page worksheet contains six problems. Answers are provided.