3299.Resource, GeoGebra (Middle-High)

This is copied directly from the website:  "Free digital tools for class activities, graphing, geometry, collaborative whiteboard and more. GeoGebra is a dynamic mathematics software for all levels of education that brings together geometry, algebra, spreadsheets, graphing, statistics and calculus in one engine. In addition, GeoGebra offers an online platform with over 1 million free classroom resources created by our multilingual community. These resources can be easily shared through our collaboration platform GeoGebra Classroom where student progress can be monitored in real time."