Activity
Ministry of Education and Universities of the Region of Murcia (Spain)

Ministerio De Educacion Y Ciencia: La Circunferencia

For Students 9th - 10th Standards
In Spanish. In this interactive activity you will get a clear understanding of the definition the circumference of a circle and have fun while learning the relationship between equations and figures.
Activity
Ministry of Education and Universities of the Region of Murcia (Spain)

Ministerio De Educacion Y Ciencia: Tangencias

For Students 9th - 10th Standards
In Spanish. This interactive unit introduces various geometric concepts which are intended to be tools for solving problems of tangencies between straight lines, circles and points.
Activity
Other

Ic Teachers: Shapes, Circles (Basic)

For Students 5th - 9th Standards
This basic website will give you lots of information about circles. There are also some questions to test your circle knowledge.
Handout
Other

Dans Math: Lessons: Trigonometry

For Students 9th - 10th
College professor Dan Bach reviews basic trig concepts, including trig functions, right triangles, circles, radians, and polar coordinates. Site includes animated graphs and detailed examples.
Activity
Texas Instruments

Texas Instruments: Equations of Circles

For Teachers 9th - 10th Standards
In this activity, students will explore the relationship among the location of the center of the circle, the radius of a circle, and the equation of a circle in a plane. They will also investigate the relationship between the points...
Activity
Texas Instruments

Texas Instruments: Math Today Coming Clean About Showering Time

For Teachers 9th - 10th
In this activity using the USA TODAY Snapshot, "Coming clean about showering time," students will find the measures of central angles and arcs of a circle. They will use circumference, radius, concentric circles and degrees in a circle...
Activity
Texas Instruments

Texas Instruments: Drawing a Line Tangent to a Circle

For Teachers 9th - 10th Standards
Students use the drawing and measurement tools of Cabri Jr. to draw a line tangent to a circle. [Requires Adobe Reader.]
Activity
Texas Instruments

Texas Instruments: Circles: Circumference and Area

For Teachers 9th - 10th Standards
The idea of perimeter can be applied not only to polygons but to circles as well. The same idea can be said for the area of a circle. (Continued. See "before the activity.") [Requires Adobe Reader.]
Activity
Texas Instruments

Texas Instruments: Real Life Real World Activity Carpentry

For Teachers 9th - 10th Standards
Carpenters use applications of geometry in their work, including the properties of right triangles and circles. This activity uses Cabri Jr. Geometry software to make measurements and solve problems based on carpentry situations....
Activity
Texas Instruments

Texas Instruments: Perimeter, Circumference, and Area

For Teachers 9th - 10th Standards
Students find perimeters of rectangles and squares, as well as circumferences of circles. Students find areas of rectangles, squares, and circles. [Requires Adobe Reader.]
Activity
Texas Instruments

Texas Instruments: Inscribing a Circle in a Triangle

For Teachers 9th - 10th
In this activity, students bisect the angles of a triangle and find the incenter of the triangle. They find the distance from the incenter to the side of the triangle and use it as radius. With the incenter as the center, they inscribe a...
Activity
Texas Instruments

Texas Instruments: Circles in the Plane

For Teachers 9th - 10th
In this activity, students can use the Cabri Jr. application to explore circles in a plane. They will investigate the relationship between the equation of a circle, the length of its radius, and the coordinates of its center. [Requires...
Activity
Texas Instruments

Texas Instruments: Picturing Probabilities of Number Cube Sums

For Teachers K - 1st Standards
Students use ideas of ratio and proportion to investigate various ways to make a circle graph. Students create graphs to display the probabilities of the different sums that can be generated with two number cubes. [Requires Adobe Reader.]
eBook
Math Planet

Math Planet: Geometry: Basic Information About Circles

For Students 9th - 10th Standards
A definition, examples, and a video lesson all help to explain basic information about circles. [0:36]
eBook
Math Planet

Math Planet: Geometry: Inscribed Angles and Polygons

For Students 9th - 10th Standards
Inscribed angles and polygons are investigated through examples and a video lesson. [0:42]
Activity
Cut the Knot

Cut the Knot!: Monge's Theorem of Three Circles and Common Tangents

For Students 9th - 10th Standards
Very good site presenting a Trig problem dealing with tangents lines and circles, then linking the student to the solution
eBook
Math Planet

Math Planet: Geometry: Advanced Information About Circles

For Students 9th - 10th Standards
Provides advanced information about circles through the use of examples and a brief video lesson. [1:00]
Unknown Type
McGraw Hill

Glencoe Mathematics: Online Study Tools: Self Check Quiz on Circles

For Students 9th - 10th Standards
Students show comprehension of advanced mathematics skills in Geometry. The questions check understanding on circles. Topics include diameters, angles, and finding the circumference.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Co Inscribing a Square in a Circle

For Teachers 9th - 10th Standards
In this lesson, students learn how to inscribe a square in a circle. Aligns with G-CO.D.13
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 7.g Stained Glass

For Teachers 7th
In this lesson plan, 7th graders use formulas for area and circumference to solve the word problem.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 7.g the Circumference of a Circle and the Area

For Teachers 7th Standards
In this lesson plan, 7th graders determine the circumference and area of a circle.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 7.g Eight Circles

For Teachers 7th
In this lesson plan, 7th graders use their knowledge of formulas to determine the area and circumference of a circle.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 7.g,rp Measuring the Area of a Circle

For Teachers 7th
In this lesson plan, 7th graders answer word problems to determine the area of a circle.
Unit Plan
CK-12 Foundation

Ck 12: Geometry: Diameter or Radius of a Circle Given Circumference

For Students 6th - 8th
[Free Registration/Login may be required to access all resource tools.] In this lesson students find the diameter or radius of a circle given the circumference. Students examine guided notes, review guided practice, watch instructional...