It must be one hell of a clock if a teacher actually told the student to hide it from plain sight!
EDIT: A picture of the actual device is here.
http://www.wfaa.com/story/news/local/dallas-county/2015/09/1... https://archive.is/Q0OLb
EDIT: A picture of the actual device is here.
http://www.wfaa.com/story/news/local/dallas-county/2015/09/1... https://archive.is/Q0OLb
http://ichef.bbci.co.uk/news/624/cpsprodpb/10BF6/production/...