http://search-engines-web.com/ submits a number of articles on high school and collegiate plagiarizing.
From the Daily News Tribune,
“With a slew of Web sites peddling pre-written term papers to students in high school and college, the Internet is dragging the ages-old practice of plagiarism into the 21st century.”
The Seattle Times, and The Eastern Echo also weigh in, along withTurnitin.
My $.02
Personally, I have a problem with services such as Turnitin. My problem is in the fact that Turnitin takes content from sites across the web without first requesting permission (yes, I see the irony in this).
Here’s how it works: Turnitin runs spiders across websites that download a copy of the pages they run across to Turnitin’s own servers*. Turnitin then compares teacher/professor submissions against these pages. The problem with this for webmasters is that this is an opt-out service, meaning that I can only prevent Turnitin from taking content from my own site by blocking them *after* they have already taken the content.
Side note: Turnitin did this in violation of the terms of my site and refused contact when I attempted to reach them.
This is essentially what Google and every search engine does, but it is a matter of intent. Google is there to help Joe User to find a document at no charge. Turnitin (and services like it) are there to provide a service and make money off of doing it.
*http://www.turnitin.com/static/faqs/technology_ faq.html