OER Commons
Oer Commons: Mars: Proving the Pythagorean Theorem
This lesson is intended to help you assess how well students are able to produce and evaluate geometrical proofs. PowerPoint slides are included with the lesson.
Texas Instruments
Texas Instruments: Visiting the Rich History of Geometry Using the Ti 92
In this activity, students study various geometric theorems.
CK-12 Foundation
Ck 12: Geometry: Parallelograms
[Free Registration/Login may be required to access all resource tools.] This concept teaches students properties of and theorems about parallelograms and how to apply them.