There apparently was a threat of some kind of harm to the school, students and teachers contained in a note, say the authorities, and although no one was harmed and no weapons found, the police did get to do a systematic search of the school grounds, lockers, and student possessions. The students were searched, made to pass through metal detectors, and herded out to the football field under the watchful care of the St. Charles police "Special Response Team".
One of the mothers in the story, expressing relief her daughter was safe, had the quote of the day:
"It's a horrible thing to get a phone call at work and learn your daughter has been targeted," she said.
I agree with the quote.