Yeah the learning is kind of progressive, so there's stuff at L2 that builds upon L1 stuff, then L3 that builds on the L2. So it makes sense to do them in order, but not everyone does!
For an Honours degree you need 360 points, at least 120 of which are at L3 and another 120 at L2 or above. The rest can be L1 or L2. I only have 60pts at L1, and when I have finished, I will have done 120 points at L3, 180 at L2 and the 60 at L1.
You can take an Ordinary degree with 300 points but I wouldn't really see the point of stopping so close to the mark of getting an Honours one - unless there were some circumstances personally affecting the decision of course.
This Page tells you about the points required for degrees - that particular page is related to the Open BSc/BA programme, but for named degrees the points/credits principle still stands (the only difference is that for named degrees there are specific courses/modules to take, for the Open one you can do whichever ones u like so long as they give you the required credits at the right levels! Phew!)
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