GeoGebra is a program designed to support the teaching of mathematics in high school. It incorporates diverse exercises and theory on calculation, algebra and geometry.
The chapter on geometry allows the student to draw and calculate different volumes and different perimeters
GeoGebra has a complete catalogue of example equations although students will be able to enter their own and analyze how the system solves them or try to do it alone to check the result later.
It includes construction of graphs, recognition of all numbers and mathematical symbols, different levels in all sections, self-assessment tests and tools for teachers.
It's an award-winning program in both the education and software development categories and the best part is that it's totally free.