This paper presents the design of the didactic strategy modeling language (DSML) according to the principles of Physics of Notations (PoN). The DSML is a visual and activity-oriented language for learning design characterized by the representation of different activities according to the nature of the task. Once the language is designed, a blind interpretation study is conducted to validate the semantic transparency of the learning activity iconography. The results of the paper allow to refine the icons. In addition to this, an authoring tool for DSML, which is integrated to an LMS, is presented. As a result, a model driven course was designed as a DSML pre-validation.