Project based learning provides an ideal pedagogical context for the introduction of interdisciplinary perspectives and the facilitation of interdisciplinary competence. However, many questions about the curriculum design and the assessment of interdisciplinary learning are not adequately answered in the literature. In this paper, we attempt to extend computer supported project-based learning into interdisciplinary curricula. The purpose is to provide effective pedagogical tools that may aid more productive interdisciplinary learning research and practices. We propose an ontology-based project mediation framework for enabling interdisciplinary learning activities and collaborative team work. Combined with problem domain knowledge and model, the framework is instantiated in a computer supported learning system, called HAM, for interdisciplinary project in the selected problem domain of digital archiving. Preliminary assessment and application results seems to show HAM?s utility to operate in an interdisciplinary pedagogical context and facilitate collaborative skills in team work.