Wow.. that is a huge task, and likely impossible to fully cover every angle. In the end, the majority of students will be honest, but there will always be a few who will try a shortcut, or just try to cheat their way through. (The kinds of people who become CEOs, Presidents or serial killers I expect... )
You may want to start with the Plugin Development documents, there is likely to be something there that will help. From there, have a look at the existing plugins in the Downloads pages. There may be something existing that you could use as a template or there may be a number of plugins that do one thing each that you could combine into a single plugin. This is likely to save you some time if find something you could use. Just make sure that the code is Open Source though, some plugins are free to use, but not Open Source, I understand.
If you are looking for serious Development support, which you may need if something is just not working, try the General Developer's Forum. Lots of help is available from existing Devs. Good luck.