A teacher contacted me this morning to see if our district's plagiarism guide was still available. Yup, the link on the website was broken (now fixed), but the document still exists. Here it is:
The guide was created about 10 years ago at the request of the HS English department. They wanted a common set of standards that addressed cheating, copying, plagiarism, and citing sources, etc.
I think the document has held up pretty well. See what you think and let me know changes needed. And yes, the document is for you to use, modify, and adopt under CC license.