Update!
A lot of the tutoring dread I felt at the beginning of this semester has disappeared! Thanks to some spectacular articles, an allstar English 3840 cast, and especially those grammar reviews Claire has had with us, I'm feeling a lot of the confidence that I so craved months ago. I am not saying I have "arrived." There is still so much more to know. What I am saying, however, is that I have hit a rhythm in which basically every session, no matter what the subject, is the same. BioMed, creative writing, developmental English, 1010, 2010, visual art, it basically doesn't matter for me. What IS more of a factor is who the student is. What kind of a person is she/he? How am I feeling that day? How is he or she feeling? I have found that the dynamics of the tutoring session are controlled more by the two people involved and how invested they are in each other and the piece of writing in question rather than the nature of the piece of writing, itself. That's where the adventure lies for me--with the people involved.
Not to totally skirt the question, however, I will say this: the subject that seems most difficult to STUDENTS, in my experience, is (well, it's not a subject, it's an assignment) the Compare and Contrast essays for the 955 students. They have seemed to find this particular task to be the hardest to figure out. Many of the 955 students are either not sure of what precisely is being asked of them (and those sessions, I admit, are perhaps a little more difficult for me because of all of the angles I have to come from in order to describe how to compare and contrast) or they have convinced themselves that, although they've finished the essay, they have done a terrible job of actually comparing and contrasting the material (which is almost never the actual case--these ones are usually very solid).
I suppose that I do have to put a little more effort into tutoring compare and contrast essays, now that I think about it, but it's still not something that I dread. Tutoring difficulty lately has been gauged by how tuned in the tutor and writer are to each other as well as how much both parties actually care about the writing in question. With both things in place, it rarely matters what subject or assignment is being discussed.