- Geometry
- Area of Circles
- Area of a Circle - Wedge/Sector Demonstration
- Discovering Pythagoras' Theorem by Area
- Area of Parallelograms (GeoGebra 4 version)
- Pythagorean Triples; 5,12,13
- Sum of the exterior angles of a convex polygon.
- Triangle Names and Angle Sum (Interior and Exterior)
- Investigating the Sum of Polygon Interior Angles
- Exterior Angle Theorem
- Angle Bisector Thm
