TELOS is a new eLearning system being built within the Canadian LORNET project. TELOS aims to provide an open operating system in which users can develop and use eLearning and knowledge management resources and environments within a service-oriented and ontology-driven framework. A special emphasis is put on the aggregation of resources through a graphic scenario editor and the referencing of the resources using a knowledge and competency representation. We advocate that this approach is necessary for federated search or harvesting tools to be well integrated and find meaningful learning resources that need to be repurposed and aggregated, taking in account the diversity of technologies, pedagogical intent and referencing schemas. Key Words. Aggregation Scenarios, Learning Resources, eLearning systems