How do you keep students from wasting time chatting or sneaking to inappropriate sites?
You teach! You have frank discussions. You show them examples and ask them to make ethical decisions. You ask: What does it mean that fifteen-year-old kids are calling themselves nineteen and posting racy pictures online? What does it mean that college kids are posting raunchy spring break pictures that a prospective employer can find? The idea that we are the stories we tell has never been more important. Schools have always taught kids how to present themselves -- that's why we did oral presentations in the classroom. Now we need to teach them to present themselves electronically. That's why it's so scary to lock these technologies out.
Answers a question I'm sure is on every teacher's mind when thinking about incorporating social networking into the classroom. Teachers need to teach students how to act, write, speak, and present themselves.