'Exponential' increase in school shooting drills since Sandy Hook

'Exponential' increase in school shooting drills since Sandy Hook  ABC News Newtown Plans Private Reflection To Mark Five Years Since Sandy Hook Shooting  Hartford Courant Commentary: Remember victims' families on 5th anniversary of Sandy Hook  Press Herald Florida Cops Terrify Students by Holding Active Shooter Drill Without Any Warning  Mediaite Kelly Elementary School Shooting Update: Two Students Injured, Not Life-Threatening, Say Calif. Police  CBS NewsFull coverage