Oswego City School District
Regents Exam Prep Center: Lines and Planes
Use these resources in preparing instruction on undefined terms (points, lines, and planes), theorems relating lines and planes, and Euclidean and non-Euclidean geometry. You'll find three lessons on the aforementioned subject areas, an...
Wikimedia
Wikipedia: Hyperbolic Geometry
This encyclopedia entry from Wikipedia offers a discussion on hyperbolic geometry. The site explains how the hyperbolic geometry plane is represented in two dimensions and how lines in the plane must be drawn. Other types of models for...
National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Hyperbolic Geometry
Dr. Math, responds to a question fro a nineth grade stduent who wants to understand hyperbolic geometry. The Dr. uses descriptive analogies in attempts to unravel why triangles in hyperbolic geometry have less than 180 degrees in them.
Wolfram Research
Wolfram Mathworld: Elliptic Geometry
MathWorld offers a brief definition of elliptic geometry and including a brief discussion of its relationship to Euclidean geometry, with links to other related definitions.
Cut the Knot
Cut the Knot!: Interactive Mathematics: Geometry Articles, Theorems, Problems
Contains over five hundred Geometry articles, problems, puzzles, and games. Some sites relating to circles are provided within this list.
University of California
University of California: Geometry in Action
This page collects various areas in which ideas from discrete and computational geometry (meaning mainly low-dimensional Euclidean geometry) meet some real-world applications.
Wikimedia
Wikipedia: Spherical Geometry
Wikipedia, a publicly-maintained encyclopedia, provides an explanation of spherical geometry along with a listing of its most important uses.
Boston University
Fractal Geometry of the Mandelbrot Set Ii
This web site addresses counting and adding in fractal operations, as well as the role of the Fibonacci sequence in fractal geometry.
Wolfram Research
Wolfram Math World: Euclid: The Elements
The classic treatise in geometry written by Euclid is presented in English. It is the textbook used for more than 1,000 years in western Europe.
Oswego City School District
Regents Exam Prep Center: Indirect Euclidean Proofs
This Oswego City School District Regents Exam Prep site shows you how to proof something by showing that it is false. This look at indirect proofs includes a practice and a teacher resource page, which features a warm-up activity.
Oswego City School District
Regents Exam Prep Center: Writing a Proof: Direct Euclidean Proofs
This site is a look into the world of geometric proofs. You'll learn what a proof is and about the different types of proofs. Try the practice page to check your understanding. Teachers can check out the teacher resources for lesson and...
Wolfram Research
Wolfram Math World: Spherical Geometry
Site provides a brief explanation of the discipline of Spherical Geometry along with many links to spherical geometry topics.
University of Illinois
University of Illinois Urbana Champaign: Torus Math: Spherical Geometry Demo
A java applet on this site illustrates the principles or spherical geometry.
Oswego City School District
Regents Exam Prep Center: Theorems and Postulates for Geometry
Here is a partial list of theorems, postulates, and properties.
Wolfram Research
Wolfram Math World: Hyperbolic Geometry
Hyperbolic Geometry is discussed here with specifics on the lines in this geometry. The equations of the lines are represented as well as a desription of the lines. The site has links to other non-Euclidean Geometries.
Math Words
Math words.com: Elliptic Geometry
The basic definition for what elliptic geometry is is found here.
Wikimedia
Wikipedia: Elliptic Geometry
This encyclopedia article contains a basic description of what elliptic geometry is.
Math Open Reference
Math Open Reference: Biography of Euclid
Biography of Euclid, a Greek Mathematician, also known as the 'Father of Geometry'.
City University of New York
Lehman College: An Introduction to Lines
Use this site for two short lesson plans regarding Euclidean and Spherical lines. Intersecting and parallel lines are discussed. The lesson contains activities for two days of class.
Jim Loy
Jimloy.com: Saccheri
This site explains the Saccheri quadrilateral and the importance of his work in geometry.
Shodor Education Foundation
Shodor Interactivate: Lesson: The Mandelbrot Set
In this instructional activity students will explore Julia sets and the Mandelbrot set. In the process they will learn about fractals and explore complex numbers and function iteration.
Wolfram Research
Wolfram Math World: Distance
MathWorld.com gives a formula for finding distance using the Pythagorean theorem. The formula for finding the distance between two points in Euclidean space is given on this page. The page has links to related topics.
Boston University
Bu: Fractal Geometry of the Mandelbrot Set
This site progresses in iterations through Mandelbrot and Julia sets to explain fractals and the mathematics behind them.
Alabama Learning Exchange
Alex: Platonic Solids Ornaments
This is a hands-on activity that introduces students to the five Platonic solids. Students will discover the special relationship between faces, vertices, and edges. Students will research the Platonic solids and then construct and...