Not sure what level of education we're talking about here, but at least in Norwegian universities lectures are mostly not mandatory. I never attend them. I do t

Not sure what level of education we're talking about here, but at least in Norwegian universities lectures are mostly not mandatory. I never attend them. I do the required work and do well on the exam. The key is that: instead of spending 2 hours on a lecture where I'm sitting there passive, maybe not paying attention and the lecturer will only give the big picture and not the details (so I still have to read up on the subjects afterwards), I instead spend 1.5h reading/doing it by myself.