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...
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...
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 worksheet provides guided practice through many topics such as central angles, inscribed polygons...
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...
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...
EngageNY
Arcs and Chords
You've investigated relationships between chords, radii, and diameters—now it's time for arcs. Learners investigate relationships between arcs and chords. Learners then prove that congruent chords have congruent arcs, congruent arcs have...
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 plan on how to use the distance formula to derive the equation of the circle. Pupils transform circles on the coordinate plane...
Curated OER
Making Models of the Solar System
Students make several models of the solar system to learn the positions of the planets in the solar system as well as relative distances and sizes. Creation of these models will help them identify the planets by size, shape, color,...
Virginia Department of Education
Arc Length and Area of a Sector
What do skateboarding and baked goods have in common with math? You can use them to connect half-pipe ramps and cakes to arcs and sectors. Pupils compare the lengths of three different ramp options of a skate park. They calculate the...
Curated OER
Pi Day: The Other Math Holiday!
Happy Pi Day! This collection of games, experiments, and activities leads participants through an exploration of the many aspects and attributes of that mysterious quantity, pi. Activities range from using statistical...
Virginia Department of Education
Angles, Arcs, and Segments in Circles
Investigate relationships between angles, arcs, and segments in circles. Pupils use geometry software to discover the relationships between angles, arcs, and segments associated with circles. Class members use similar triangles to...
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...
Mrs. Burke's Math Page
The Amazing Pi Race
Add a sense of excitement to your math class with this race across the country. Using their knowledge of all things circular, young mathematicians work in pairs answering a series of pi-related word problems as they hop from one city to...
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
Worksheet for Pi
Who needs a pie-eating contest when you have a pi-ology game! Celebrate March 14th with a fun board game about pi and other geometric concepts. As learners answer questions about geometry, they move around the board to collect...
101 Questions
Car Caravan
Keep playing with those old toy cars! Pupils estimate the number of toy cars in an art installation. The only information they receive is a picture showing the toy cars arranged in concentric rings and the diameter of the overall...
Curated OER
Lesson Plan Outline for Rainbow Science
Young scientists study light reflection and refraction as they determine the critical angle, the rainbow angle, and color separation in rainbows. Teams record the data they collect in a shared spreadsheet and discuss results with the class.