Eva-CBTM is a project for the Evaluation of Computer Based programs for learning and Teaching Mathematics. The idea of Eva-CBTM is to develop a complete system for such an evaluation which is valid, reliable and objective. The evaluation system is based on a process oriented view at computer based practicing of mathematics. The system has the following components: assessment, assistance resp. help, architecture of the system, system of choosing exercises, and degrees of freedom. The consideration of thematic completeness plays an important role in the evaluation process. In the first two chapters over 60 platforms for learning and practicing mathematics are presented in short, 15 of them are fully evaluated. Chapter III discusses the potential of platforms for presenting more complex tasks, for instance problem solving or modeling. Chapter IV describes a method to measure the "didactical comprehensiveness" of CBTM-platforms, i.e., the depth in which a certain topic is dealt with in exercises.