Use plagiarism detection tools such as AntiCutAndPaste and/or MOSS (Measure Of Software Similarity) to easily discover if any of your students are cheating off of one another.

Both MOSS and AntiCutAndPaste catch common plagiarism tactics such as changing variable/ parameter names.
AntiCutAndPaste also catches changes in comments, and spacing.
MOSS:
- reports that X% of Student A’s submission is a match for Y% of Student B’s submission.
  - It produces a side-by-side mapping of Student A and Student B’s code, with matching sections highlighted in color.
  - Typically, a potential case of plagiarism will result in over 50% matching, while a non-plagiarism case will be around 10-15% matching.
- Check out the free MOSS tool for more information.
  - Note from the CS Teaching Tips Team: MOSS is compatible with C, C++, Java, C#, Python, Javascript, Lisp, Scheme, Matlab, and more!
AntiCutAndPaste:
- reports plagiarized lines of code so you don’t have to dig through student files after seeing the report.
- Check out the free AntiCutAndPaste tool, available for Windows and Linux!
  - Note from the CS Teaching Tips Team: AntiCutAndPaste is compatible with C++, Visual Basic, Delphi, Java, C# and plain text.

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