We investigate in this paper the instructional design rationale of open pedagogical scenarios. We use the Domain-Specific Modeling (DSM) approach for proposing Domain-Specific Educational Modeling Languages (DSEML) and dedicated editors to teachers/designers in order to allow them to work at a high-level of abstraction. Thanks to EMF tools we have realized a first implementation of our proposal about learning sessions of Hop3x. The Hop3x’s DSEML is described by a metamodel and accordingly a first version of specific editor has been generated.