Like everyone else, I've been following the news about the word "scrotum". Head over to Fuse #8 for links and discussion. Apparently, LM-Net, a listserv I don't belong to, was discussing this so I both joined and began to search archives.
And that's when I learned about Julie Amero, the substitute teacher facing 40 years of prison for exposing students to pornography on the Internet (story at the New York Times.)
From what I've read, Amero had the following bad luck: she didn't know much about computers, the school was not up to date with filters, no other teacher helped her out, and pop ups (spyware/ adware) took over the classroom computer. Here's a column on the case from the Hartford Courant. Also read Questionable Conviction of Connecticut Teacher in Pop-up Porn Case.