Looking at numerous examples of triangles, each with different properties, geometers develop their understanding of congruency. They use the notation of a counter-example to disprove certain conjectures and prove geometric theorems and...

More of a mini-unit than a lesson, these activities lead inquisitors through a survey of oil deposits. In the first part, they read about and view diagrams of sedimentary rock layers that trap oil. Next, they test porosity and...

Students explore the concept of ellipses. In this ellipses lesson, they construct ellipses on their paper and follow directions on a worksheet that allow them to investigate an ellipse in more depth by looking at the major axis, foci, etc.