A Classroom Glass Question Sparks a Larger Debate About School Safety Priorities

Editor's Note: NCSSD members whose comments are included in this article gave permission for their remarks to be shared anonymously.

A recent discussion among National Council of School Safety Directors (NCSSD) members began with a practical question about classroom glass but quickly expanded into a larger debate about how schools should prioritize safety investments when time, money, and personnel are limited.

An NCSSD member said his district is addressing what they described as "glass issues" at one of its high schools. The building has few places where students and staff can conceal themselves during a lockdown, and the district has identified some glass areas that could be frosted to reduce visibility into those spaces.

The issue has been a concern among staff, students, and parents since the building opened in 2019, the member explained. The district is considering having occupants of certain rooms move to designated frosted rooms during a lockdown and is also determining what should be communicated to students and families about those plans.

They asked other NCSSD members how districts with similar building designs have addressed the issue, including what they communicated to families, whether they explained where students would hide, and whether those plans generated pushback.

Members Suggest Ways to Address Classroom Glass

Several members offered potential approaches. One suggested looking beyond frosting and considering whether glass could be replaced or upgraded with shatter-resistant or ballistic-rated materials based on the threat being addressed. Another pointed to the Partner Alliance for Safer Schools (PASS) guidelines for information about security glazing and window film.

Other members suggested perforated film that allows occupants to see out while limiting visibility into the room, interior blinds, security film designed to delay entry, and blackout-style shades that can be deployed during a lockdown.

The discussion also raised potential drawbacks. One member questioned whether moving students from one classroom to another during a lockdown could expose them in a hallway. Another asked whether frosting the glass could reduce visibility during normal school operations and whether students and staff would also be moved away from the “fatal funnel,” the vulnerable area near a doorway or other point of entry, rather than relying primarily on concealment.

As members discussed possible solutions, the conversation shifted from how to address glass to a more fundamental school safety question: How should districts decide which vulnerabilities warrant investment?

How Much Should Schools Invest in Low-Frequency Threats?

One member argued that every security measure should be subject to a cost-benefit analysis. Schools have spent millions of dollars on measures such as bullet-resistant glass, the member said, even though someone shooting through glass is extraordinarily rare. That raises questions about how much schools should focus on one particular danger and how far they should go to mitigate it.

The cost, the member argued, isn't limited to dollars. Schools also have to consider the time, personnel, and stress associated with security measures, along with the opportunity cost of spending resources on one risk rather than another.

The member cautioned that the image of an attacker entering a classroom is so vivid and frightening that it can seem more likely than other scenarios that are actually more common. They argued that the balance between spending on physical security measures and investments in human supervision and prevention has become heavily weighted toward physical security.

That prompted a counterargument. Another member said percentages can be misleading when discussing the protection of children and compared preparations for school violence with protections against fire.

"We don’t decide whether to install fire alarms or sprinklers based solely on the percentage of children who die in school fires, because we understand that prevention and preparedness save lives," the member wrote.

Low-frequency, high-consequence events still warrant reasonable precautions, they argued, because the consequences of being unprepared can be irreversible.

"The question shouldn’t be whether a threat is statistically common enough to justify protection, but whether we can reasonably reduce the risk when the consequences are catastrophic."

The Opportunity Cost of School Safety

The first member returned to the question of limited resources.

"Your points are well taken and make a strong argument when we have unlimited dollars and a balanced approach," they wrote.

Schools, they argued, are spending billions on reactive measures of questionable value while neglecting prevention. They again used the fire analogy, asking readers to imagine schools being unable to afford fire alarms because all available money had been spent on sprinklers.

"We have to consider the opportunity cost of every safety measure," they said.

The responding member agreed that opportunity cost matters but argued that schools should not treat prevention and physical protection as an either/or proposition.

"Fire alarms, sprinklers, prevention, and physical security all serve different purposes," they wrote. "The goal should be a layered approach that prioritizes measures based on the threat and the potential consequences."

Another member joined the discussion and said the two perspectives were largely in agreement. A child killed in a parking lot, they noted, is just as much a tragedy as a child killed inside a classroom. Schools therefore need to look objectively at how they allocate limited resources and avoid allowing school safety decisions to be driven by lobbying or sales pitches.

"We want to prevent school shootings and all shootings," they wrote. "We want to protect as many kids (and adults) as possible with the limited resources that we have."

Prevention and Protection Aren't Mutually Exclusive

Others continued to emphasize that prevention and protection do not have to compete philosophically, even when they may compete for funding.

"Prevention and protection are not mutually exclusive," one member wrote. "A layered approach means we do both."

Schools can work to prevent violence while also preparing for the possibility that prevention will fail, they argued.

Their concern was that discussions about school safety can become centered on what districts cannot afford rather than what communities are willing to prioritize. If a reasonable last line of defense could save lives during an active threat, the member questioned why schools would not want to provide it in as many classrooms as reasonably possible.

Bringing the Debate Back to Classroom Glass

The member who started the discussion eventually provided additional context about their district's decision. The district already has prevention and preparedness measures in place, they said, including what they described as a culture and climate focused on safety and security. The district is not planning to install bullet-resistant film.

Instead, it is trying to solve a specific vulnerability in one building.

"We aren’t installing bullet-resistant film. We are installing film so that students and staff can hide during a lockdown," they wrote. "As it stands now, this building has nearly zero place to hide in a lockdown."

They also emphasized that they were not interested in spending money on the "latest and greatest" security product and believed culture and climate play a significant role alongside physical security.

But the district still has to address a practical problem.

"We have to address the issue of nowhere to hide if we are teaching SRP," they wrote.

While members differed on how schools should prioritize limited resources, there was general agreement that prevention, preparedness, and physical security all have a role in school safety. Much of the debate centered on how schools balance those investments while addressing vulnerabilities specific to their buildings and communities.