Texas Instruments
Texas Instruments: Isosceles Triangle
In this activity, students construct isosceles and equilateral triangles. They discover that if two sides of a triangle are congruent, then the angles opposite them are congruent. They understand that an equilateral triangle is also...
CK-12 Foundation
Ck 12: Geometry: Triangle Classification Grade 8
[Free Registration/Login may be required to access all resource tools.] Classifying triangles by using angle measures and side lengths.
Math Open Reference
Math Open Reference: Triangles
A complete reference guide to types of triangles and triangle perimeter and area. It provides definitions and interactive animated activities that enhance further explanation.
Oswego City School District
Regents Exam Prep Center: Geometry Vocabulary Resources
A list of geometry definitions and a matching activity.
Alabama Learning Exchange
Alex: Tan Ii
The Chinese character mark for Tan II (pronounced she-tow-bah) is the second of two lessons to introduce first grade students to geometry using tangrams. This instructional activity incorporates history, math, and language arts. In this...