Research Design Help: Measuring the effects of plagiarism intervention
I am just improvising on the fly here but does Korea have software like TurnItIn which measures (in a few different ways) the level of plagiarism in a particular paper or a set of papers usually from online sources. 

If you do, then you could think about devising an experiment where, in a class, you inform the students that you will be trying to reduce their "plagiarism tendencies" and take a pre-test perceptions survey. Next, you set a particular class paper as an assignment and note the different measurements on TurnItIn (or equivalent). Then, you make your intervention (in whatever form you choose) and finally set another class paper as an assignment and note the different measurements on TurnItIn this time. Finally, you set a post-test debriefing and follow up survey.

I think this would make for a very nice repeated measures model (from the TurnItIn or equivalent data) and some nice latent variable analysis from your surveys.

I hope this helps you in some meaningful way.