Interdisciplinary grants should involve faculty from two or more different disciplines who are committed to team teaching and to addressing problems of significance to students, the University, the nation, and/or the world. Project courses can be either general education or cross-listed requirements/electives for majors.
A good literature review, including definitions and a chapter dedicated to interdisciplinary teaching, can be found at The Higher Education Academy.
Additional resources developed by the Higher Education Academy Interdisciplinary Teaching and Learning Group in the UK can be found at http://www.heacademy.ac.uk/ourwork/networks/itlg.
Highlights of an interesting faculty panel discussion can also be found at http://ctl.stanford.edu/Newsletter/interdisciplinary.pdf.