Bulletproof whiteboards, concrete school barriers, video surveillance and armed teachers.
Those are just some of the security measures schools have taken since the Dec, 14, 2012, shootings at Sandy Hook Elementary School in Newtown, Conn. that killed 20 students and six educators.
"It's not just Sandy Hook. We experienced this after Columbine and after Virginia Tech. People tend to implement knee-jerk reactions," said Robin Hattersley Gray, executive editor of Campus Safety Magazine.
Nationwide, about 1 out of every 4.5 million school kids between the ages of 5 and 18 is killed each year at school or getting there and back, according to the Bureau of Justice Statistics. That works out to about 10 to 30 kids a year, or about 1 percent of all kids who are killed. That rate held steady from the early 1990s to 2011, the most recent year available.
Since Sandy Hook, schools immediately tightened their security. A 2013 survey by Campus Safety Magazine found 88 percent of respondents from K-12 schools said they made or would make changes to their security and emergency management programs because of Sandy Hook.
But it's unclear how big of an impact those changes had.
Since December 2012, there have been at least 74 school shootings in the U.S., according to the website Everytown, which has tracked shootings in school buildings or on school or campus grounds based on media reports.
Whether the rate of school shootings has increased or decreased since before Sandy Hook is unknown because K-12 schools are not required to report shootings.
Among the more common changes schools implemented were lockdown drills, upgrades to locks and doors, and single entrances to buildings, Gray said.
Demand for training of school resource officers has also doubled in the year after Sandy Hook compared with the year before the shootings, said Kevin Quinn, president of the National Association of School Resource Officers.
Currently, an estimated 10,000 SROs work at K-12 public schools, Quinn said.
Quinn said efforts to arm school staff, like teachers and custodians, is not the answer.
SROs often have years or even decades of experience and are trained to make split-second decisions, he said.
"You don't bring more guns to reduce gun violence," Quinn said.
Even with SROs and security guards, schools need to have emergency plans and staff members that "keep your ear to the ground" about what's happening in the schools, he said.
School staff is more prepared in how to talk about these tragedies with students, as well as to identify warning signs, said Jill Cook, assistant director of the American School Counselor Association.
"The human things we can do are going to be much more effective than the technology or bringing in more guns," said Curtis Lavarello, executive director of the School Safety Advocacy Council.
Contributing: Paul Overberg
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