The dynamic mathematics software Geonext establishes new ways of teaching and learning mathematics. It offers opportunities of visualisation that can't be realised on paper or blackboard and with traditional construction tools. Geonext enables autonomous and cooperative learning of mathematics in the classroom. It encourages an active discovering approach to mathematical thinking. Geonext can be used at school and at home for free (GPL). Therefore the software can be handed out to students without any copyright problems (GPL). Geonext can be used from elementary school up to calculus at high school and in teacher-training at university in a manifold and flexible way. WWW: http://www.geonext.de -Andreas Fehlner fehlner@gmx.de