If you see something definitely plagiarized, you could try to get them to claim it as theirs when they consult you and fail them on the spot for making the claim whether it's in class or not.

I do agree with @DaveClarke that on this or the other issue, announcing a policy at the start of the term (no more than N consults per assignment/per term, and plagiarism is an automatic F and will also be referred to the school's academic conduct team) would help set expectations, cut down on abuse, and give you grounds to say "No, it wouldn't be fair to others if I helped you again before you turn it in."

What to do about students who ask for help too often?
I heard there are 620 letters in the Aseres Hadibros which corresponds to the 613 Mitzvos of the Torah and 7 Mitzvos D'Rabanan. What are the Seven Mitzvos D'Rabanan - שבע מצוות דרבנן? Is there a easy way to remember them? Is there any disagreement as to what the seven are?
