Re:
http://chronicle.com/weekly/v55/i06/06a12001.htmIf a student opens a newspaper, web browses on a laptop, or does text messages in class, I immediately interrupt the lecture to request that the behavior cease. It has not happened often, and it never happens twice in a semester. I won't continue a lecture while a single student behaves in this manner. The other students don't deserve to be subjected to a distracted professor, merely to save the guilty from embarrassment.
If you're worried about teaching ratings, just consider that the increase of respect will likely offset any drop from the offending student. And if not, so be it. Life is too short to put up with that behavior.