At Wolcott High School one morning this week, an urgent announcement crackled over the intercom: a threatening intruder was in the building and students were told to immediately take refuge in classrooms. Doors were locked and police, with dogs, moved in. Students stayed huddled in classrooms where they were told to stay away from the windows. But what sounded like a frightening situation was just a search for narcotics. Drug-sniffing dogs combed the school while students stayed in locked classrooms, believing that an attacker was roaming the halls. Drug-free schools are an admirable goal but I wonder when we reached...