An eMathTeacher is an eLearning on–line self–assessment tool that helps users to active learning math concepts and algorithms by themselves, correcting their mistakes and providing them with clues to find the right solution. This paper introduces an example of a new concept on Computer Aided Instruction (CAI) resources, i.e. a tutorial designed under eMathTeacher philosophy for active eLearning Mamdani’s Direct Method, and presents a brief survey on available CAI resources discussing what their influence over students’ behaviour is. It also describes the minimum and complementary requirements an eLearning tool must fulfil to be considered an eMathTeacher as well as the main contributions of this kind of tutorials to the learning processes. Needless to say that, such features as interactivity, visualization and simplicity turn these tools into great value pedagogical instruments
