I found this to help when in school as well as college. I would always find a POI (point of interest). Meaning, something I liked about each subject, and I would find myself expanding from one thing to another while in that subject. I, for one hated math, but found a way to try to use it daily, and slowly it became more interesting. Not much, but enough to pass with a satisfactory grade. It might take you a little while, but there is something is each subject that is bound to interest you, even if it is you trying to "disprove" something taught in the subject. I have done that many times, and found myself learning.