Here's the situation: The paper is due tomorrow and you've already read and responded to student drafts a week ago. A student whose draft was barely there asks you to look over another draft just in case he missed anything. You quickly skim his draft, note tremendous improvement except for a few format and grammar problems, and then get the sinking feeling that part of this work was copied and pasted from somewhere else. How do you respond?
1. Google the suspicious passage, locate the online source, and tell the student he's getting an F on the paper and you're writing him up for plagiarism.
2. Google the suspicious passage, locate the online source, and warn the student that he'd better rewrite the plagiarized sections before submitting the paper for grading.
3. Send the student an e-mail (paper trail!) reminding him of the importance of properly punctuating and citing sources and suggesting that if he has unintentionally (!) copied and pasted from online sources without proper punctuation and citation, he will get an F on the paper. Then Google the suspicious passage, locate the online source, and wait for the student to submit the paper for grading so you can pounce on the plagiarized passages and give him his well-deserved F.
Some sub-points to consider:
a. Would the level of the course affect your answer? (First-year vs. sophomore vs. upper-level?)
b. Would the time of year affect your answer? (First major assignment vs. final paper?)
c. Would your previous experience with the student affect your answer? (Reliable but rushed student vs. committed slacker?)
I know how I would deal with this because I've just done one of these three things this week, but one of the occupational hazards of thinking for a living is that I never stop second-guessing myself. So let me know what you would do and then I'll share what I actually did.