EngageNY
Experiments with Inscribed Angles
Right angles, acute angles, obtuse angles, central angles, inscribed angles: how many types of angles are there? Learners first investigate definitions of inscribed angles, central angles, and intercepted arcs. The majority of the...
EngageNY
Inscribed Angle Theorem and Its Applications
Inscribed angles are central to the lesson. Young mathematicians build upon concepts learned in the previous lesson and formalize the Inscribed Angle Theorem relating inscribed and central angles. The lesson then guides learners to prove...
EngageNY
The Angle Measure of an Arc
How do you find the measure of an arc? Learners first review relationships between central and inscribed angles. They then investigate the relationship between these angles and their intercepted arcs to extend the Inscribed Angle Theorem...
West Contra Costa Unified School District
Arcs and Angles
Noah didn't construct this kind of arc. High school scholars first explore how angles can be formed in circles. They then learn relationships between angles and arcs by conducting an exploratory activity where they position and draw arcs...
EngageNY
Unknown Angle Problems with Inscribed Angles in Circles
We know theorems about circles—now what? Class members prove a theorem, with half the class taking the case where a point is inside the circle and half the class taking the case where a point is outside the circle. The lesson then...
Texas Instraments
Angles in Circles
Teach your learners how to investigate the relationship between a central angle and an inscribed angle which subtend the same arc of a circle. The dynamic nature of Cabri Jr. provides opportunity for conjecture and verification.
Curated OER
Measurement of a Central Angle
Learners calculate the measurement of a central angle. In this geometry lesson, students identify properties of circles. They use Cabri software to create and analyze graphs.
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...
Royal Society of Chemistry
Shapes of Molecules—Distortion from the Pure Geometry
Ready to introduce the realities of molecular geometry to chemistry pupils? Use a logic-based interactive! Perfect as individual practice, the puzzles explore the bond angles and repulsions present in three common molecular shapes.
EngageNY
Solve for Unknown Angles—Angles and Lines at a Point
How do you solve for an unknown angle? In this sixth installment of a 36-part series, young mathematicians use concepts learned in middle school geometry to set up and solve linear equations to find angle measures.
Curated OER
Geometry Circles
In this circle worksheet, students find the measure of identified angles. Students are given the measurement of arcs and of the central angle in a circle. This two-page worksheet contains 45 problems. Answers are provided on page two...
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 activity provides guided practice through many topics such as central angles, inscribed polygons...
Royal Society of Chemistry
Shapes of Molecules—Geometry of Central Atom
How is a molecule's shape determined? Explore bond angles, lone pairs, and VSEPR theory through a logic-based activity. Chemists pull together information about the major molecular shapes, then use it to solve puzzles.
Mathematics Vision Project
Module 5: Circles A Geometric Perspective
Circles, circles, everywhere! Pupils learn all about circles, central angles, inscribed angles, circle theorems, arc length, area of sectors, and radian measure using a set of 12 lessons. They then discover volume formulas through...
EngageNY
Arc Length and Areas of Sectors
How do you find arc lengths and areas of sectors of circles? Young mathematicians investigate the relationship between the radius, central angle, and length of intercepted arc. They then learn how to determine the area of sectors of...
Curated OER
Inscribed and Central Angles in a Circle
In this geometry activity, students find the missing angle that is inscribed inside of a circle. They define vocabularies related to the circle. There are 17 questions.
Curated OER
Arc Measurement Based on The Measurement of a Central Angle
Students define keywords that are important to solve problems. In this geometry lesson, students find the arc length and angle of a circle. They convert between radians and degrees.
Texas Instruments
Cabri Jr. Inscribed and Central Angles
Learners will differentiate between inscribed and central angles in this geometry lesson. They answer questions dealing with circles as they relate to inscribed triangles and angles. This assignment includes a printable worksheet.
Curated OER
Quiz: Angles and Arcs in Circles - Central and Inscribed
In this angles and arcs in circles worksheet, students determine the angle and arc measurement in a circle from given information. This one-page worksheet contains ten problems.
Inside Mathematics
Hopewell Geometry
The Hopewell people of the central Ohio Valley used right triangles in the construction of earthworks. Pupils use the Pythagorean Theorem to determine missing dimensions of right triangles used by the Hopewell people. The assessment task...
EngageNY
Geometry Module 5: Mid-Module Assessment
How can you formally assess understanding of circle concepts? Pupils take a mid-module assessment containing five questions, each with multiple parts.
Curated OER
Tile Patterns I: Octagons and Squares
This can be used as a critical thinking exercise in congruence or as a teaching tool when first introducing the concept. Four octagons are arranged in such a way that a square is formed in the middle. With this information, geometry...
Curated OER
Quiz: Area of Sector and Segment
In this area of sector and segment worksheet, students find the area of a shaded sector. Given the central angle of a segment and the radius, students identify the area of a sector. This one-page worksheet contains ten problems.
Curated OER
Polygons - Sum of Interior Angles
In this polygon worksheet, students determine the sum of the interior angles of a figure. Given the sum of the interior angles, they determine the number of sides of a polygon and the measure of one central angle. This one-page worksheet...