"study high, take the tests high, get high scores"

Love that phrase from the film
all i can say is that anyone that thinks it's the way forward to smoke a blunt or whatnot instead of doing your work, well you're just silly and should not be surprised by where your life decides to take you as a result.
You decide you need the grades you didn't get this time around later on in life, you gotta restudy from scratch, that's another couple of years of education because of a lack of self-diciplin
as said, do your work, then smoke as a reward for having done it.