Interactive
Curated OER

Angles and Arcs formed by Intersecting Chords

For Students 9th - 11th
In this angles and arcs instructional activity, students complete a warm-up, state the formula formed by intersecting chords, and answer eight problems.  The instructional activity includes a closing think pair share problem.
Lesson Plan
Virginia Department of Education

Angles, Arcs, and Segments in Circles

For Teachers 9th - 11th Standards
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...
Lesson Plan
Curated OER

Perpendicular Segments in a Circle

For Teachers 9th - 12th Standards
High schoolers explore the concept of circles as they construct a circle using a program such as Cabri Jr. Learners construct a chord and a diameter that are perpendicular, then measure the bisected chord and notice that both sides of...
Lesson Plan
Curated OER

Segments Formed by Intersectiong Chords, Secants, and Tangents

For Teachers 9th - 12th Standards
Learners investigate the properties of segments formed which chords, secants, and tangents, intersect. The dynamic nature of Cabri Jr. allows high schoolers to form and verify conjectures regarding segment relationships.
Worksheet
Curated OER

Congruent Chords, Parallel chords and Perpendicular Chords

For Students 10th - 11th
In this geometry learning exercise, students solve problems about congruent, parallel, and perpendicular chords and bisectors.  There are 9 problems with an answer key.
Worksheet
Curated OER

Arc and Angles Formed by Secants and Tangents

For Students 9th - 11th
In this calculus worksheet, students solve problems by finding the line of tangency and measure of the arcs and angles form by a secant line. There are 9 questions.
Lesson Plan
Curated OER

Circle, Secants

For Teachers 9th - 11th
Students identify the secant segment of a circle. In this geometry lesson plan, students investigate secant lines formed outside the circle. They use Cabri software to create drawings and explore circles and secants.
Lesson Plan
Curated OER

Chords of a Circle

For Teachers 10th
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.
Worksheet
Curated OER

Geometry Review

For Students 10th
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,...
Worksheet
Curated OER

Parts of the Circle

For Students 6th - 8th
In this geometry skills worksheet, students respond to 3 questions that require them to examine the part of circles and identify them as diameters, chords, radii, or centers.
Worksheet
Curated OER

Parts of the Circle

For Students 5th - 7th
In this geometry skills worksheet, students examine 3 labeled circles and identify the noted items as diameters, chords, radii, or centers.
Lesson Plan
Curated OER

Equations of Circles

For Teachers 10th - 12th
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.   
Worksheet
Curated OER

Circle Problem

For Students 9th - 12th
In this geometry worksheet, learners calculate what the maximum number of regions are that 8 chords can divide a circle. They follow a pattern to arrive at their answers. There is an answer key with this question.
Worksheet
Curated OER

Circles

For Students 10th
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...
Worksheet
Curated OER

The Center of a Circle

For Students 10th
For this center of the circle worksheet, 10th graders solve 5 different center of the circle measurements. First, they draw a circle and add two points on it. From there, students construct a line segment and a midpoint on the line...
Worksheet
Curated OER

Geometry Regents Bimodal

For Students 9th - 10th
In this geometry activity, students solve problems that are bimodal. They define properties of circles and triangles. There are 117 questions.
Worksheet
Curated OER

Circles

For Students 9th - 10th
In this geometry worksheet, learners solve problems by finding the diameter, radius and chord of a circle. They also solve for the area of the circle. There are 10 questions with an answer key.
Lesson Plan
EngageNY

Secant Angle Theorem, Exterior Case

For Teachers 9th - 12th Standards
It doesn't matter whether secant lines intersect inside or outside the circle, right? Scholars extend concepts from the previous activity to investigate angles created by secant lines that intersect at a point exterior to the...
Lesson Plan
EngageNY

The Inscribed Angle Alternate – A Tangent Angle

For Teachers 9th - 12th Standards
You know the Inscribed Angle Theorem and you know about tangent lines; now let's consider them together! Learners first explore angle measures when one of the rays of the angle is a tangent to a circle. They then apply their...
Lesson Plan
Curated OER

Intersecting Lines and Segments of Measures

For Teachers 8th - 12th Standards
Mathematicians measure intersecting lines-and circles, and create chords. In this geometry lesson plan, students explore interrior and exterior chords created by tangent and secant lines. These segments can be inside the circleor outside...
Lesson Plan
Curated OER

Chords of a Circle

For Teachers 9th - 12th Standards
Teach how to differentiate between chords and perpendicular bisectors. In this geometry lesson, students relate the properties of chords and circle to solving right triangle. They define what makes two chords congruent in side a circle.
Worksheet
Curated OER

Chords of Circle

For Students 10th
In this geometry activity, 10th graders solve problems using parallel chords, perpendicular bisectors and chords that are equal distance from the center.
Lesson Plan
Curated OER

Product of Chord Segments

For Teachers 9th - 10th
Students creating chords intersection using circles. For this geometry lesson, students create visuals of chords ad their properties using Cabri technology. They measure the chords and explore the relationship among chords.
Lesson Plan
Curated OER

Circle Conjectures

For Teachers 9th - 11th Standards
Students are given diagrams and are asked to make a conjecture. In this geometry lesson, students make conjectures of circles. They complete a lab activity to reinforce making conjectures. The first activity addresses a common core...