[ghufran_syed]

I think the cost is so low because they are providing the absolute minimum in terms of a degree - curriculum, and marking of assessments and exams. In fact, you even pay for them separately, so you can pay some amount ($800?) In September to register for the year on 4 courses (which is full time, equivalent to 30 semester units in the US), and get access to the whole curriculum. Then you can decide by Feb the following year which exams you want to do, and only pay for the ones you want to do that year, which is around $300 per exam. You are mostly self taught, though there are some online forums with teaching staff available to answer questions.