School lockdowns become more frequent

School lockdowns, and preparing for a possible intruder, have become a fact of life for many metro Atlanta schools.

On Wednesday, DeKalb County school officials locked down five schools because of criminal and police activity near those campuses. Fulton County ordered a lockdown of two schools when robbery suspects were on the loose.

School safety has changed in recent years with horrific mass shootings such as the 2012 incident at Sandy Hook Elementary School, where 20 students and six staff members were killed by a gunman, still fresh in the minds of many Americans. In most cases, a school lockdown is ordered by a principal or school resource officer when there are armed suspects nearby or a fight between students gets particularly violent. In less urban areas, lockdowns have been ordered when a hunter errantly encroaches on school property.

How do officials decide when to lockdown a school? What happens when a school is locked down? Are school officials being overly cautious?

Read more about the answers to those questions here.