We present a novel software for the acquisition of central components of number processing and representation as well as mathematical understanding. The software is based on current neurocognitive concepts and insights. The learning process is supported through multimodal cues encoding different properties of numbers. The learning environment features 3D graphics and interaction components and thus allows immersion in a playful 3D world. To offer optimal learning conditions, a Bayes net user model completes the software and allows adaptation to a specific user. A first version of the software will be tested with normally achieving and dyscalculic children within a multi-center study in Zurich, Berlin, and Potsdam starting in 2011.