I have an Open university course, but I'm doing it in conjunction with my A-levels, it is worth a menial number of points and won't be included in any university offers I doubt. But to answer your question, it's really not a heavy workload (is yours the degree module thing, rather than a proper degree course), I just got a textbook, information and you answer a few essay questions. Assuming you're talking about the same course, it's not that heavy a workload.