So tired of it I'm apathetic, but not too tired to abstain from passive aggressiveness (these are all from the same class):

Mr. Economics: So... you've never done a paper in this discipline before. Hmmm... you weren't there on the day that I spelled out what I was expecting on the paper proposal? That excuses this pile of crap you're wondering why you got an F on? Interesting. But you seem so engaged now that you are in my office hours. Sure, I'll spend and hour and a half explaining as much as I can for you and helping you craft your topic and thesis. Sure, why not get a second chance at the proposal. Oh, excellent! I look forward to your paper so I can see how I have made a difference. Oops! A copy and pasted, badly plagiarized final paper? Awesome! My favorite! At least you don't blame me for your F and still smile happily and say "Hi, Professor!" around campus. No bs, it's kind of refreshing not to blamed for a student's crap.
Ms. I Don't want to be here: Who are you? Are you in my class? Oh! right. Hmmm... didn't recognize you because you never show up. Oh, some help with the paper? Sure... A half hour later, and I look forward to reading your paper. Interesting topic. Nice. At the next department meeting, I am warned that you may only be here to get away from your parents and that you are a problem plagiarizer. Well, I will reserve judgement. Awesome! You didn't plagiarize in an obvious way! Instead, you used one source and basically summarized the one argument from that text, mis-labeling page numbers and other innocuous forms of bad citation. Nice. You and Blondie should get together and talk about how neither of you handed in any of the weekly assignments and are both sharing the same grade! Life is awesome for you.
But to make up for it:
Ms. Studiously Intriguing: Random references, on topic, to BDSM, yaoi, anime and a host of other fascinating cultural topics that you somehow make relevant to class material? Who knew it was possible? Wait, you are not a major? Hmmm... and you surpass all the majors in class because of your hard work and diligence to make yourself knowledgeable about the topic? And you get the material and challenge yourself to go beyond it? What? Why aren't you in all my classes? A is made of Awesome!