Educators on edge as children go back to school in U.S

(Reuters) - Cautious educators and police locked down schools at the first hint of trouble on Monday as nervous parents sent their kids back to school for the first time since the massacre at Sandy Hook Elementary School in Newtown, Connecticut.

Educators fearful of "copycats" or troublemakers who might phone in empty threats grappled with how to respond and whether to discuss Friday's shootings with children.