Those who pick and eat had better beware.
Seriously though, if there was ever an infringement on the privacy rights of people, this is it. This needs to be nipped in the bud once and for all.
This is not it. Children have no reasonable expectation of privacy in a public school except in the bathroom. The teachers, as public employee's in a public institution, have no reasonable expectation of privacy, except in the lounge and restrooms as well.
What are you? One of those "Living Constitution" types!