Explain plagiarism to your students. Students are sometimes told not to plagiarize, but have no idea what plagiarism is. One of the more common assumptions made by students is that plagiarism is simply copying a book or an article word for word. They sometimes assume that if they change a few words here and there or if they slap quotation marks on the beginning and end of the sentence that they have avoided plagiarism. Students need to clearly understand that plagiarism can involve taking someone's idea as their own without providing attribution. It can also involve stringing together endless quotes from a text and calling it a research paper.
Show your students multiple examples of plagiarized papers. Showing them what to avoid and how to avoid it will go much further than just telling them about it. Provide them with a handout and discuss it in-depth during class. Encourage and allow them to ask questions to clarify any points they don't understand.
Create a stern policy for dealing with plagiarism. Educators are usually constrained by the limits of what their school's institution will allow. Let your students know that you will handle any and all instances of plagiarism to the greatest extent that you are allowed. In some colleges, this can mean expulsion. Provide a step-by-step policy of how you will deal with any instances of plagiarism.
Require students to submit their papers to plagiarism-detection software. Websites like Turn It In can help you eliminate plagiarism from the classroom by automatically detecting any work that appears to be copied from the Internet or has previously been submitted by another student as a research paper at another college or university. Explain to students how the website works and how you will use it to determine whether or not they have plagiarized. Equipped with proper knowledge about what they are up against, most students will shy away from the temptation to plagiarize their paper.