Can I smoke weed and still get good results? Watch
If you are feeling deadly stressed (as I often did during A-levels) then the immediate relief of marijuana is a welcome feeling. I would not discourage using it in any way, since it works and it is effective. On the other hand, I would say perhaps seek out more long-term stress relief. St John's Wort, whilst mild, can be effective when used over long periods of time, and likewise for prozac. This is only because it would save you money over that time and you would not run the risk of being caught possessing and consuming a class B drug.