Bull! It’s a college course if you are failing you have to cut down on the parties and study. Ten percent passed it so it is not an impossible task!! I think the 90% are probably either hunkering down or have dropped the course, either way her class will improve considerably.
I teach college, and if 90% of my class is failing, I do something differently. I have high standards and my students must work hard in my class, but if they’re missing it, then I need to change my technique.