National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math Alternate Exterior Angles
Dr. Math at the Math Forum offers a way of remembering alternate exterior and alternate interior angles by looking at the words and realize what they say and apply it to the picture.
ClassFlow
Class Flow: Angles in Geometry
[Free Registration/Login Required] This flipchart is a look at angles in geometry. Drawing, labeling, measuring, special angles: (right, straight, acute, obtuse) and congruence.
ClassFlow
Class Flow: Angle Facts
[Free Registration/Login Required] This lesson is a thorough review of all types of angles (e.g. obtuse, right, scalene, isosceles, equilateral, alternate) with wonderful diagrams to reinforce thinking skills.
Math Open Reference
Math Open Reference: Parallel Lines
Get the definition for parallel lines and explore angles associated with parallel lines.
Math Open Reference
Math Open Reference: Alternate Interior Angles
Explore the triangle inequality theorem with this helpful reference tool. Provides a detailed definition and an interactive activity that enhances further explanation. Includes links to related topics.
Math Open Reference
Math Open Reference: Alternate Exterior Angles
Learn about alternate exterior angles with this handy reference guide. Provides a detailed definition and an interactive activity that enhances further explanation. Includes links to related topics.
Texas Instruments
Texas Instruments: Parallel Lines Cut by a Transversal
In this activity, students learn and increase their knowledge about the angles formed when parallel lines are cut by a transversal.
Math Words
Math Words: Alternate Interior Angles
This site offers a definition for alternate interior angles with a labeled graph and links to other related words.
Math Words
Math Words: Alternate Exterior Angles
Alternate exterior angles are defined with a labeled picture and one of such pairs of angles are exemplified.
Arizona State University
Arizona State University Horn Studio: Henri Kling and the Valved Horn
This ASU biographical sketch depicts a man in the 1800's who was consumed by French horn music. As a composer and conductor, he viewed music from many angles. His beliefs about the playing of the French horn are interesting and...
Alabama Learning Exchange
Alex: Build a City on Geometry
The students will be split into small, cooperative groups and build a city following specific guidelines. The students will learn how a city is constructed with angles, intersections, parallel, intersecting, and transversal streets. They...
ClassFlow
Class Flow: Bearings 2
[Free Registration/Login Required] This is a flipchart introducing student to compass bearings. It can be followed by flipchart bearings going further in depth of bearing orientation.
Sonoma State University
Sonoma State University: Parallel Lines and Similar and Congruent Triangles
This site defines parallel lines, parallel lines cut by a transverse, and congruent triangles. It also contains links for related terms.
Geometry Help
Geometry Help: What Are Parallel Lines in Geometry?
Explains the basic concept of parallel lines in Geometry with step-by-step instructions and methods for solving specific problems on your own relating to this topic.
Wolfram Research
Wolfram Math World: Conformal Mapping
This site explains what conformal mapping is, gives alternative names used in reference of this transformation, uses pictured examples to emphasize the particulars of the definition, gives an if statement with regards to conforming...
Math Open Reference
Math Open Reference: Areas by Slicing
Learn about alternate exterior angles with this handy reference guide. Provides a detailed definition and examples that enhance further explanation. Includes links to related topics.
Curated OER
Etc: Proposed Isthmian Canal Routes, 1848 1884
A map of the proposed isthmian canal routes in Nicaragua and Panama between 1848-1884. The map shows the two chief proposals, the Nicaraguan from Greytown on the Caribbean to Lake Nicaragua and Brito on the Pacific, and the Panama...