In the last decade, e-learning has been introduced to a variety of blended learning scenarios, such as life-long learning, University lectures, and game-based learning. In all these scenarios the learner's situation or context is an essential asset in designing the learning process. Recent research suggests aiding the design process through the use of visual modeling approaches. Pervasive computing environments particularly call for extending these approaches in terms of enhanced context-awareness. This paper addresses these needs by introducing a UML-based modeling extension for explicitly including relationships between context and learning activities in the learning design models. The feasibility and applicability of our approach is demonstrated by a laboratory lecture case study, and respectively by a context-aware learning prototype that was developed using RFID technology for sensing of nearby persons and physical resources.