Check out this insightful article by an educator who deals with student plagiarism: Plagiarism: To Steal or Not To Steal. Of particular note is the author’s recognition of student’s not setting out to plagiarize (see “Accidental Plagiarism”) as well as the importance of teacher’s modelling good reading skills (which she terms “curiosity”) in the classroom to dissuade student’s from plagiarizing and become original writers who think critically.