My research colleagues and I have launched a new website where people can test their comprehension of BPMN models at http://www.bpmn-selftest.org/. The website is part of a research project of HU Berlin and TU Eindhoven.
We would be very happy if you participate and advertise the selftest among your colleagues. Its unique feature is that you get BPMN models shown along with questions. In the end you get immediate and individual feedback on what you did right and wrong. There is also a draw for some prizes.