"Robert Dickow" <[email protected]> wrote: > > > Speaking of 'audio' classroom tricks, I have recently heard about one that I > don't think I have caught my students doing yet, but it is intriguing: > ......... Has anybody been able > to confirm this?
Have you heard of the opposite technique, developed as an ultrasonic teenager repellent. Oldies don't even notice but youngsters feel the pressure and move on. Ouch! http://www.nytimes.com/2006/06/12/technology/12ring.html Simon V _______________________________________________ post: [email protected] unsubscribe or set options at https://pegasus.memphis.edu/cgi-bin/mailman/options/horn/archive%40jab.org
