A good rule of thumb is to average 2-3 hours out of class studying for every hour spent in class. For the more difficult classes, that number can be even highe

A good rule of thumb is to average 2-3 hours out of class studying for every hour spent in class. For the more difficult classes, that number can be even higher. So for a class that has 3 hours of lecture time per week, that's 9+ hours per week on that subject alone.