While the tablet PC is a very valuable addition to teaching in a college setting, I can't imagine the chaos if a public school system just gives laptops to students at the high school level or lower. I would bet that many of the laptops will simply disappear, be damaged or stolen in the first few weeks and the rest will be used primarily to look at Internet porn and download music files instead of being seriously used in classes.
But, even at the law school level, I've been told by people sitting in the back that the laptops are used for anything but notetaking. IM, internet, email, etc.
Now, I'll plead guilty to keeping outlook in the background, and if an interesting or critical email comes through, I read it, but the simple fact of the matter is that my mind is boggled that people don't pay attention in class.