Everyone learns the number one rule about triangles in high school: the angles of a triangle add up to 180 degrees. But did you know that sometimes they don't? Triangles are much more interesting than ...

Big Idea – We can describe, measure, and compare spatial relationships. to build on students' knowledge of triangle and to develop students' reasoning with properties of triangle to develop students' ...

Circles, triangles and squares. One of the first things we learn as children are basic geometric shapes. And they stay with us throughout our lives. Maybe it’s that sense of familiarity that makes ...