EngageNY
Writing the Equation for a Circle
Circles aren't functions, so how is it possible to write the equation for a circle? Pupils first develop the equation of a circle through application of the Pythagorean Theorem. The activity then provides an exercise set for learners to...
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...
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...
EngageNY
From Circle-ometry to Trigonometry
Can you use triangles to create a circle? Learners develop the unit circle using right triangle trigonometry. They then use the unit circle to evaluate common sine and cosine values.
Curated OER
Tangent Lines and the Radius of a Circle
Your Geometry learners will collaboratively prove that the tangent line of a circle is perpendicular to the radius of the circle. A deliberately sparse introduction allows for a variety of approaches to find a solution.
EngageNY
Construct a Square and a Nine-Point Circle
Anyone can draw a square, but can you CONSTRUCT a square? Here is a resource that challenges math scholars to create steps to finish their own construction. They test their ability to read and follow directions to complete a construction...
Dick Blick Art Materials
Start with a Circle...
The Golden Ratio. The Divine Proportion. Yup. It's math and art blended into one colorful activity. Young artists combine colored tissue paper circles and parts of circles to create geometric patterns. As a bonus, kids get to figure out...
Curated OER
Construction Circles
Pupils investigate the number of points needed to determine a unique circle in a plane. Using Cabri Jr., they apply construction techniques to generate a circle that passes through a given number of points.
Curated OER
Chords of a Circle
In this geometry worksheet, 10th graders calculate the length of a chord and the distance from the center of a circle or radius. They compare diameter, chords and radius. There are 10 questions with an answer key.
EngageNY
Unknown Area Problems on the Coordinate Plane
Scholars determine distances on the coordinate plane to find areas. The instructional activity begins with a proof of the formula for the area of a parallelogram using the coordinate plane. Pupils use the coordinate plane to determine...
Curated OER
Equations of Circles
Using Cabri Jr. students construct a circle and determine the equation of the circle they drew by finding the center and the radius. Students use the distance formula to derive the equation of their circle.
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
Geometry and Geoboard
Sixth graders use geoboards and dot paper to experiment with geometric concepts. In this geometry lesson, 6th graders complete four activities using geoboards or dot paper including naming points on a coordinate plan and finding the area...
Curated OER
Circles to Spheres
Students investigate circles and spheres. In this space shapes lesson plan, students compare and contrast two-dimensional and three-dimensional shapes. Students investigate the relationship between plane and space shapes.
EngageNY
Properties of Tangents
You know about the tangent function, but what are tangent lines to a circle? Learners investigate properties of tangents through constructions. They determine that tangents are perpendicular to the radius at the point of tangency,...
Curated OER
Branding Circles, Squares, Rectangles, Triangles
Compare and classify 2-D shapes! Kindergarteners inspect the attributes of plane shapes and examine shapes in everyday life. They label the circles, squares, rectangles, and triangles they find. This is the website where you can find the...
Illustrative Mathematics
The Geometry of Letters
Use the alphabet as a tool for teaching your class about geometric figures. Break apart capital letters into line segments and arcs. Classify angles as right, acute, or obtuse. Identify parallel and perpendicular lines. An excellent...
Curated OER
Geometry in the Real World
Eighth graders complete a unit of lessons on basic geometry concepts. They participate in a variety of activities, culminating in a project that involves publishing a booklet or a poster that presents the major geometry concepts from the...
Curated OER
Spherical Geometry: A Global Perspective
Students investigate spherical geometry using a globe and an apple. In this spherical geometry lesson plan, students translate Euclidean geometry terms to spherical geometry terms using a globe. They answer 3 questions about spherical...
EngageNY
Modeling Video Game Motion with Matrices 2
The second day of a two-part lesson on motion introduces the class to circular motion. Pupils learn how to incorporate a time parameter into the rotational matrix transformations they already know. The 24th installment in the 32-part...
Curated OER
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.
Curated OER
Shapes...the Beginning of Geometry
Students identify and name basic shapes and points. In this elementary geometry lesson, students use printable cut outs to name circles, triangles, and squares before playing a game with them. They play a game of "Pin the Tail on the...
Curated OER
Exploring Area/Perimeter Through Coordinate Geometry
Students explore area and perimeter through coordinate geometry using student literature, hands-on manipulatives, and the Internet.
Curated OER
Shapes in Our World
Help your learners explore shapes. They classify shapes and identify them in their everyday world. Plane shapes are explored, and they classify and identify the plane shapes.