I don't know why they're not the same but, my theory is that it might be to do with OU students often not having conventional entry qualifications. So, by having seemingly "higher" scores, it's less discouraging. Maybe? I mean, why are brick university grades so low?
Search on clevernet ou degree classification to predict your final degree
The scores for the TMAs/exams are done differently. 85+ is a distinction, for example, whereas at the brick uni I went to 70 would have been a 1st.
They then also take the lower of the TMA average (perhaps with substitution applied to raise it slightly) and exam score as your mark.
Then they have another formula for working out the degree classification. You multiply the grade for each level 2 module by the number of points it was worth and multiply your grade for each level 3 module by double the number of points it was worth, then add the two totals together. Then there's a bunch of tables to consult to see what your degree classification is (you have to look at the right one for the amount of credits you'll be claiming with the OU). Then, they look at the classification you've been awarded and I think also check that at least two fo your level 3 modules were at that grade or higher (if not they drop you down a classification).
Hiya I just got the result back for my first TMA I got a 60 which I'm pretty disappointed about - I think! I did a credit transfer at my previous uni a 60 would have been a 2:1 is it a 2:2 at the OU? Why is it different and has anyone got a link of scores to degree classifications so I can see what I need to get in the future. Thanks x