Shooting instructor Johnny Price looked at the teachers lined up in front of him. Mr. Price, the owner of Big Iron Concealed Handgun Training in Waco, Texas, spent two days this month training teachers and staff members from the Clifton school district in all they need to know to earn licenses to carry weapons out of sight. There is no indication that the 1,000-student district is leaning toward allowing employees to bring guns to school. But curiosity about carrying concealed weapons has been running high here and all over the country ever since the school shootings in Newtown, Conn., on Dec. 14. The massacre has given rise to the perhaps once-unthinkable idea of arming teachers as a possible policy fix for improving school safety. While many national organizations have rejected the idea, it is now being seriously weighed by some school boards and state lawmakers across the nation.