Purple Math
Purplemath: Converting Between Radians and Degrees
Describes degrees and radians with respect to angles, the reason for the invention and use of radians, and how to convert between radians and degrees.
Savvas Learning
Pearson Education: Radian and Degree Angle Measures [Pdf]
This resource details how to convert between radians and degrees with worked examples. It also looks at special radian measures that are used often.
Khan Academy
Khan Academy: Radians and Degrees
Convert angle measures given in degrees to radians and vice versa. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Radians & Degrees
Convert angle measures given in degrees to radians and vice versa.
Google
Google for Education: Degrees and Radians
Students label key points on the unit circle in both radians and degrees. They count their way around the circle in 30-degree increments, and then again in increments of radians. Finally, students go through a similar process for angles...
BBC
Bbc: Radians and Equations
BBC provides a tutorial that explains how radians are related to degrees and demonstrates how to solve trig equations in radian units. Examples and a practice test are available.
Windstream
Ojk's Precalculus Study Page: Measurement of Angles
An introduction to radian measurement, including converting between radians and degrees. Includes several examples and lots of pictures.
Interactive Mathematics
Interactive Mathematics: Radians
Learn the definition of radians and how to calculate trig ratios using radian measures. Examples are provided showing how to convert from degrees to radians.
Interactive Mathematics
Interactive Mathematics: Angles Degrees and Radians
Angles are key to Trigonometry. Learn definitions of the parts of an angle, degrees, and radians, identify the standard position of an angle, convert between radians and degrees, and more.
Other
Teachers Choice: How to Convert Degrees to Radians or Radians to Degrees
This site offers a discussion on radian measure. The site offers pictures and explanations to clarify the formulas given. (Note: The free download at the end of the page will not work in archived version of site.)
Varsity Tutors
Varsity Tutors: Hotmath: Practice Problems: Degree and Radian Measure
Twenty-four problems present a variety of practice working with degree and radian measure. They are given with each step to the solution cleverly revealed one at a time. You can work each step of the problem then click the "View...
CK-12 Foundation
Ck 12: Algebra Ii: 4.4 Radians
This section introduces radians an alternative to degrees as a way to measure the rotation around a circle. It also begins to draw connections between radians and trigonometric identities.
Mathigon
Mathigon: Geometry: Circle and Pi: Degrees and Radians
Rather than dividing a circle into some number of segments (like 360 degrees), mathematicians often prefer to measure angles using the circumference of a unit circle - a circle with radius 1. This way of measuring angles is called...
CK-12 Foundation
Ck 12: Trigonometry: Conversion Between Degrees and Radians
[Free Registration/Login may be required to access all resource tools.] This lesson introduces the unit circle and radians.
Lawrence Hall of Science
The Math Page: Trigonometry: Radian Measure
Here is a site that clearly and thoroughly explains the radian measure of angles. There are example problems solved, problems for the student to attempt, and answers to the student problems.
CK-12 Foundation
Ck 12: Geometry: Arcs and Angles Study Guide
This study guide on arcs and angles covers key vocabulary, arc measurement in degrees and radians, congruent arcs, bisecting arcs, and the angles on, inside, and outside a circle. Also covers formulas and theorems. It is available for...
Northeast Parallel Architectures Center, Syracuse University
Npac Reu Program: Conversion
This site displays the formulas for the simple conversions of degrees to radians and radians to degrees. Near the bottom of the page there are examples of these conversions.
National Council of Teachers of Mathematics
Nctm: Illuminations: Pi Fight
Become comfortable with using both radians and degrees.
CK-12 Foundation
Ck 12: Trigonometry: Conversion Between Degrees and Radians
[Free Registration/Login may be required to access all resource tools.] Express a degree measurement in radians.
Illustrative Mathematics
Illustrative Mathematics: F Tf.1 What Exactly Is a Radian?
For this task, students use a piece of string or another tool to measure the radius of the circle and then mark off the corresponding arc length on the unit circle as many times as they need to for 0, 1, 2, 3, 4, 5, and 6 radians. They...
University of Colorado
University of Colorado: Ph Et Interactive Simulations: Trig Tour
Take a tour of trigonometry using degrees or radians! Look for patterns in the values and on the graph when you change the value of theta. Compare the graphs of sine, cosine, and tangent.
University of Vienna (Austria)
The Graphs of Sin, Cos, and Tan Maths Online
This applet allows the user to create the graphs of sin, cos, and tan by moving a scroll bar. The user can watch the unit circle and the graph simultaneously to see how the two are related. The user may also choose to see the angle...
Interactive Mathematics
Interactive Mathematics: Trigonometric Functions
Just about everything you need to know about trigonometry can be found here. Interactive examples and demonstrations help to enhance the lessons. Although not required, the tutorial uses Live Math and Scientific Notebook.
Math Is Fun
Math Is Fun: Unit Circle
Students learn about the unit circle. Topics include degrees, radians, and Pythagoras' Theorem. The tutorial consists of notes and examples.