LOCKDOWN

Used by most school districts nationwide when an armed intruder enters a school building or grounds, the protocol directs staff and students to:

■ Sound a lockdown alert

■ Lock classroom doors

■ Turn out the lights

■ Hide in a far corner of the classroom

■ Remain calm and quiet inside the building and wait for help

■ Not make independent decisions during the emergency

ALICE

Standing for “Alert, Lockdown, Inform, Counter, Evacuate” and used in about 300 school districts nationwide for its “enhanced lockdown options,” the program:

■ Authorizes staff and students to actively make decisions and take action to save their own lives as a crisis unfolds

■ Recommends locking down in a secure room if possible

■ Trains students to barricade classroom doors with furniture

■ Trains students to evacuate the building whenever feasible, including from windows

■ Includes a controversial “counter” component that instructs students, if all else fails, to throw objects, confuse and even physically attack the shooter

SOURCES: Massachusetts Juvenile Police ­Officer’s Association; Response Options