Instructional Video2:24
CK-12 Foundation

Segments from Secants and Tangents: Lesson

9th - 11th
Squaring the length equals the product of the outside times the whole. The presentation shows how to find a missing length in a tangent segment or secant segment. As part of a geometry playlist, the video provides the formula relating...
Instructional Video3:10
CK-12 Foundation

Angles On and Inside a Circle: Lesson

9th - 11th Standards
A video introduces methods to find the measure of angles whose vertex is on and inside a circle. Within examples, the section of a larger playlist on basic geometry incorporates several angle measurement theorems.
Instructional Video1:43
CK-12 Foundation

Inscribed Quadrilaterals in Circles: Lesson

9th - 11th Standards
Find supplementary information about inscribed angles. A section of a large geometry playlist introduces the relationship of angles in an inscribed quadrilateral. The presentation works through examples that use the relationship between...
Instructional Video3:15
CK-12 Foundation

Arcs in Circles: Lesson

6th - 11th Standards
Taking a major look at arcs is not minor. A segment of an extensive playlist on geometry introduces the concept of an arc in a circle. The resource demonstrates how to find the measure of an arc and defines special types of arcs.
Instructional Video4:16
CK-12 Foundation

Parts of Circles: Lesson

6th - 10th
Start off with the basic parts. The section of a larger playlist covering essential geometry concepts identifies and provides the definitions of the basic parts of a circles. Using drawings, the video illustrates the different parts and...
Instructional Video4:59
CK-12 Foundation

Chords in Circles: Lesson

8th - 11th Standards
Strike a chord with four theorems. The segment of a playlist on geometry introduces four basic theorems about chords in a circle. Theorems include the relationships between diameters and chords, congruent chords and arcs, and congruent...
Instructional Video4:14
Socratica

How Do You Find the Center of a Circle?

9th - 12th Standards
The center of the circle is the center of attention for the resource. A brief video in the Socratica Geometry playlist shows how to find the center of a circle not on the coordinate plane. The method here is to construct the...
Instructional Video7:20
Veritasium

The Brightest Part of a Shadow Is in the Middle

9th - 12th Standards
Shed some light on the nature of shadows! Science sleuths investigate a 200-year-old theory that light will form a bright spot in the center of a sphere's or circle's shadow with a video from Veritasium. The resource explains the...
Instructional Video11:12
Numberphile

Tau vs Pi Smackdown

9th - Higher Ed
Who wins the tau vs pi debate? Two mathematicians share their view of whether tau or pi is better in a video from the Numberphile Pi series. Spoiler alert: Pi wins.
Instructional Video3:14
Numberphile

Calculating Pi with Real Pies

9th - Higher Ed
Pie is great for finding pi. A short video shows how to use real pies to calculate pi. The method involves laying out pies along the circumference and along the diameter of a circle, and then finding the ratio of the number of pies.
Instructional Video1:57
FuseSchool

Equation of a Circle

9th - 12th Standards
Explore the equation of a circle by examining its key features. A thorough video lesson compares the equation of a circle to its graph by isolating the center and radius. After presenting the standard form of the equation, learners...
Instructional Video7:56
1
1
Math Antics

Circles, Circumference and Area

4th - 8th Standards
Put pi to work. The video provides the formulas for the circumference and area of circles. Using the formulas, the presenter shows how to distinguish the two using units. The discussion leads to the second formula for finding the...
Instructional Video7:58
1
1
Math Antics

Circles, What Is Pi?

4th - 8th Standards
Understanding the basic of circles is as easy as pi. The resource introduces the definition of a circle along with its dimensions, circumference, diameter, and radius. Using graphics, the video shows the approximation of pi and how to...
Instructional Video1:49
3Blue1Brown

A Curious Pattern Indeed

9th - 12th Standards
1, 2, 4, 8, 16, 31 ... hold it, that does not seem right. The resource presents the pattern of the number of sections created in a circle by connecting ever-increasing numbers of points on the circle. The video points out that the...
Instructional Video1:20
MinutePhysics

Proof Without Words: The Circle

9th - 12th
Showing is better than telling in a short demonstration video to find the area of a circle. The silent narrator transforms the circle, made from ball chain, into a triangle you can measure with a ruler, labeling quantities each...
Instructional Video2:07
Little Baby Bum

Shapes Song: Circle Song

Pre-K - 2nd Standards
Bright colors and a calming singing voice make up a music video highlighting a shape—the circle. 
Instructional Video7:40
PBS

Are Prime Numbers Made Up?

10th - Higher Ed
Is math real? Scholars first learn about the Goldbach conjecture and prime numbers as an introduction to the philosophical idea of whether numbers actually exist. The video continues on to use an example of a circle to consider math from...
Instructional Video11:32
PBS

When Pi is Not 3.14

10th - Higher Ed
Isn't pi supposed to be constant? An intriguing video shows how the value of pi can change when the definition of distance varies. It explains how using various L^p metrics, where p = 2 represents the traditional Euclidean metric,...
Instructional Video2:19
Little Baby Bum

Shapes Song

Pre-K - 2nd Standards
Sing along to a simple, yet informative, music video featuring eight shapes—square, circle, triangle, rectangle, star, heart, oval, and diamond.
Assessment8:43
Mathed Up!

Area and Circumference of Circles

8th - 10th Standards
Don't go around and around, help your class determine amounts around and in a circle with a video that connects circumference to the perimeter or the distance around an object. The resource includes 14 questions dealing with circles and...
Lesson Plan1:00
Mathematics Assessment Project

Modeling Motion: Rolling Cups

9th - 12th Standards
Connect the size of a rolling cup to the size of circle it makes. Pupils view videos of cups of different sizes rolling in a circle. Using the videos and additional data, they attempt to determine a relationship between cup...
Instructional Video6:48
Krista King Math

Equation, Center and Radius, and Intercepts of a Circle

9th - 12th Standards
Working with standard equations is essential to mathematics. The instructor shows pupils how to apply the equation of a circle to determine the center, radius, and intercepts of a circle. Learners then view three examples that...
Instructional Video4:01
Krista King Math

Intersecting Chords of Circles

9th - 12th Standards
Strike a chord with your classes! Use the video to demonstrate the relationship between intersecting chords in a circle. The instructor includes an example that involves a quadratic equation and extraneous solution. 
Instructional Video6:52
Krista King Math

Intersecting Tangent and Secant Lines of Circles

9th - 12th Standards
Interpret and apply the relationships between tangent and secant lines. The instructor explains the relationships of the angles and segments created by intersecting tangent and secant lines.