By nearly all accounts, the staff and students at Sandy Hook Elementary School did everything right on Dec. 14--and with the security measures they took before that day--when a young man armed with powerful weapons blasted his way into the school. But the deadliest K-12 school shooting in American history, a day that President Barack Obama has called the worst of his presidency, has revived debate over how best to ensure that schools are safe for students. The proposals include arming teachers and principals and resurrecting and bolstering an expired federal ban on assault weapons. A number of state lawmakers have said they will--or have--introduced legislation to allow school employees to carry weapons or to ease rules against concealed weapons on school grounds for people with valid permits. Arming more people, especially school staff members, drew sharp criticism from many in education, however, including teachers' unions and principals' associations. President Obama, likewise, seemed unconvinced that additional weaponry was the best solution. The debate brought renewed attention to one rural Texas district's policy of allowing some employees to carry weapons, including firearms.