Consider Your Academic Discipline
Is your academic discipline itself in transition? Are younger professors doing different kinds of research than those who've been established in their professions for many years? Is the style of their arguments different?
What kinds of methodologies are being used and what does your professor use in his own work? Does he or she expect you to use the same kind of techniques? Has your professor assigned topics like this one for a number of years or is he or she experimenting with a new approach, more open to exploring a wider range of responses?
What kinds of evidence do professionals in your discipline find most convincing? For instance, a philosophy professor might well be convinced by an argument that relies solely on logic without any tangible evidence. On the other hand, an engineering professor might require a mathematical or physical model.
Take the time to brainstorm about what you've learned about the professor to help you meet his or her expectations. You probably know much more than you think and asking questions will help you to remember details about how he or she expects the material to be treated.