It depends on what book it is. How much more do i have left? if it's a short book then i might finish it up. Is it a "classic" or for a challenge? then i may go ahead and try to tough it out. I'm currently not in school but i know i used to be required to finish those books! If B handed me one i'd also probably try to finish even if i didn't like it, at least to be able to say why. Otherwise, i've really got no problem dropping a book. The worse it is the faster i would probably stop.