University of St. Andrews (UK)
University of St. Andrews: Non Euclidean Geometry
The University of St. Andrews in Scotland provides an excellent site explaining Non-Euclidean geometry.
Cuemath
Cuemath: Euclidean Geometry
Explore the world of Euclidean geometry by understanding euclidean and non-euclidean geometry, the postulates and axioms, and how to apply them while solving problems. Check-out the solved examples for better understanding and try your...
Mathigon
Mathigon: Euclidean Geometry: Geometric Construction
This lesson focuses on the history of geometric construction beginning with Euclid's Axioms to the simple tools such as the straight edge and the compass.
Mathigon
Mathigon: Euclidean Geometry: Introduction
Mathematicians in ancient Greece were amazed by mathematical patterns, and wanted to explore and explain them. They began to study mathematics just "for fun" without a specific application in mind. One of these mathematicians, Thales of...
Mathigon
Mathigon: Euclidean Geometry: Euclid's Axioms
This lesson focuses on Euclid's Axioms, simple, intuitive statements, that everyone agrees are true. An axiom(or postulate) is a mathematical statement that is regarded as "self-evident" and accepted without proof. A key part of...
Mathigon
Mathigon: Geometry: Euclidean Geometry: Definitions
This lesson focuses on Euclidean Geometry terminology; such as line, point, line segment, congruence, circle, radius, ray, and more. It defines each term and provides an example of each.
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...
Dartmouth College
Dartmouth College: The Different Styles of Euclid and Copernicus
A history of the differences between Euclid's and Copernicus's methods of proving geometric ideas.