From the Government Technology article:
The Lake County School District's safety team is ready to activate a new security system that scans millions of social media postings for potential threats at public schools, if the School Board votes Monday night to approve it.
The proposed Social Sentinel software searches public posts on Facebook, Twitter, Instagram and other social media for suspicious words that could signal a potential incident in any county public school. The program uses a proprietary algorithm that searches for key phrases, say "kill" or "bomb," which would trigger an immediate alert to the school system's safety office. Schools officials can choose to investigate — or act swiftly to coordinate with local police if needed.
"I was on the lookout for this kind of service," said Jimmer Roy, the district's safety and security specialist. "They're one of the only products out there that do what they do."