Officials say there is no way to prevent such a tragedy, but there are protocols to help lessen the impact, should a situation like this happen here.
Fresno County Superintendent Larry Powell says, "While that's 3,000 miles away, it feels like it's here, and that's what I want folks to understand. It's like a kick in the stomach for any school administrator, because it's our greatest fear, losing a kid. Parents send us their most treasured resource, their children."
It's a tragedy no school official ever wants to live through, but they all agree you can never be too prepared.
Fresno Unified Superintendent Michael Hanson says, "You're always trying to figure out what's next. Is the access to my roof on my buildings locked, so there's no one on my roof? When's the last time we swept all hallways? How are my campus assistants deployed?"
The state requires all schools to have emergency procedure guides in every classroom, but that doesn't always defend against outside people looking to do harm.
"What we don't have control over are these random people that come on campuses," says Powell.
Fresno County schools do have an alert system should an armed intruder, or any intruder, enter campus.
Powell says, "Lock the doors, cover the windows and then get the kids down and out of the line of fire."
In the last five years, Fresno Unified has invested in doors that have peepholes and can lock from the inside. Some high school campuses have security officers, and most campuses have limited access. Powell says this might be the time to start taking even more safety precautions.
"The time for fully locked gates, for video and things may be at hand."
Powell says, "We've started to look at school safety in a whole different fashion. It's not just our kids getting skinned knees and things like that. We have to do everything we can to limit the damage. "
Fresno County students and teachers take part in three lockdown drills a year. Officials say they may now start doing those exercises once a month to make sure everyone is as prepared as they can be.
Superintendent Powell also stresses that kids need to know what to do in a situation like this, in the case a teacher is not available.