In distance education, the academic worth of courses and programmes of study are denoted by their credit rating. Yet the method of estimating the credit rating may differ from institution to institution and thus may not be an accurate representation of the work load that a distant learner is expected to shoulder. This article presents the findings of a research study conducted in the Open University of Sri Lanka to estimate the credit rating of selected courses in the Postgraduate Diploma in Education programme. The findings indicate that discrepancies that exist between expected and actualnumber ofhours devoted to study by students with differing background characteristics.