Educational assessment based on games will be an increasing part of testing programs in future, they provide promising possibilities for more valid and reliable measurement of students skills as compared to the tradi- tional methods of assessment like paper-and-pencil tests. Recently, Cognitive Diagnostic Models (CDM), that include information about how well students perform on the underlying knowledge and cognitive processing skills required for answering problems, have attracted attention. In this talk we present illumina, a game-based portal whose item mod- els are based on some CDMs. The portal let to monitor the students progress in order to make recommendations about what student needs to reinforce, but also what is ready to learn.