On campuses throughout the Bay Area, it was math and phonics as usual Monday -- although in the back of teachers' minds, the tape of the horrific shootings in Newtown, Conn., ran, over and over.
School leaders assured parents that their campuses have in place security devices and protocols -- ranging from visitor sign-in requirements to lockdown practices for students. But even as they expressed confidence in those measures, school officials also were reflecting on how they could improve them.
Valley Christian Schools in San Jose quickly plugged what it saw as a hole in its security: On Monday, it added an armed guard to its elementary school staff.
After Columbine, the private school began posting armed guards at its junior high and high school campus. School officials didn't believe the elementary school was as vulnerable, Chief Operating Officer Steve McMinn said. "We've had our opinions changed in a hurry."
The three campuses, which together have 2,400 students, also will boost other measures intended to buy time and reduce casualties in case of an attack.
In general, public schools are looking not for the elusive shield to guard against every possible threat, but a way to better prepare staff members to defuse explosive human interactions, channel students and families to appropriate help and spot early warnings of disaster.
"Anyone with a kid was severely shaken up on Friday," said Jason Willis, assistant superintendent
California schools lack the sophisticated protection systems Newtown had installed. Besides, weather and suburban design led to open campuses difficult to insulate from the outside world. And then there's the sobering reality: Sandy Hook Elementary's electronic and mechanical safeguards didn't deter a gunman who blasted through a locked outer door and killed 26 at the school.
Thus many California schools see as critical tools an alert and trained staff, engaged students and involved community.
"I think it's obvious that a determined individual with assault weapons who knows how to use them is going to overcome any defenses that we could practically have at a school site," said Troy Flint, spokesman for the Oakland Unified School District.
With its open campuses and unlocked doors, it's not difficult to gain access to many of Oakland's public schools. The district has its own police force with more than a dozen officers, plus other campus security officers.
In the West Contra Costa School District, newer schools have security cameras and all campuses are surrounded by fences or structures, spokesman Marin Trujillo said. Administrators and others patrol campuses to guard against intruders, he said.
But in the South Bay, many campuses are unfenced or have multiple entry points not easily blocked. "I don't think the community wants our schools to look like prisons, where we have barbed wire fence or metal detectors," said Chris Funk, superintendent of the East Side Union High School District. Still, the district's 11 comprehensive high schools all have surveillance cameras and police on campus. All students and staff are supposed to carry a photo ID badge.
East Side, like many other districts, last week sent parents emails and auto-dial phone calls to express condolences, offer support in helping children cope and reassure parents about security procedures.
The Hillsborough School District, coincidentally had just revising its safety plans, Superintendent Anthony Ranii said. Still, it's taking a look at them again. But, he said, "obviously any time a tragedy like this occurs, we look to see if there are any lessons we can learn."
How well security protocols work depend on staff. Last year at Morrill Middle School in San Jose, teacher Robert Wright noticed a suspicious person in the yard. For 45 minutes he tried to alert various people in the school office. "I just got voice mail and none of my calls were returned," he said.
Events short of a tragedy put district procedures through a dry run. On Monday, an anonymous caller to Sequoia Middle School in Pleasant Hill threatened "You're next" -- in an apparent reference to Friday's shooting in Connecticut.
The middle school and adjacent elementary campus were immediately placed on lockdown until Pleasant Hill police determined 30 minutes later that there was no threat.
The Cupertino Union School District is reviewing security in the wake of not only the Newtown killings, but also a scare Thursday after graffiti threatening a Monta Vista High School teacher was discovered. Both Monta Vista and nearby Lincoln Elementary were shut down for the day for security.
Santa Clara County sheriff's deputies and Berkeley police increased patrols around schools Monday. "The idea is for it to be reassuring," Berkeley Police Chief Michael Meehan said.
Like other schools, Berkeley Unified said it has a good security plan. After six students were discovered with guns on campus in 2011, the district reworked school entrances and hired more security.
"The real issue is vigilance and watching strangers, and for people to stop someone and challenge them and check their identification, and send them back to the office," school district spokesman Mark Coplan said.
Berkeley principals met over the weekend to talk about how to address the Connecticut shooting with their students.
Amid the precautions, officials said it's important to remember that school shootings, while horrific, are rare. "The chances of something like this happening are vanishingly small," said Kevin Skelly, superintendent of the Palo Alto Unified School District. Schools, he said, are the safest places kids can be. ¿"In a free and open society, we want to have schools that are open places that invite community."
And that adult-student connection, officials say, is critical.
"When your school is considered a community, and parents know teachers, and teachers know students by name, it's like having eyes in the back of your head," said Funk of East Side Union. "Everyone's out there taking care of each other."