Districts Are Investing Billions in School Safety: Here’s What Actually Keeps Students Safe

This blog is part of the Transforming Schools series, which shares effective practices and foundational research for educators, students, families, and policymakers who are reimagining schools as places where students are safe and can thrive academically, socially, and emotionally.

American schools spend more than $4 billion every year on physical hardening measures, including metal detectors, surveillance cameras, and weapons detection systems, to try to keep students safe. But the evidence that these investments work is thin, and in some cases, evidence shows they may lead to greater harm. This spring, many U.S. school administrators will make purchasing decisions investing in further school hardening. Unfortunately, in the name of keeping students safe in school, they may unintentionally be doing the opposite: deploying technologies that erode the trust, belonging, and psychological security that researchers say are the actual foundations of a safe school.

Meanwhile, research consistently points to a different answer: The most successful strategies to prevent violence aren't hardware based—they depend on students feeling connected, trusted, and supported.

The school safety technology used in schools today has expanded well beyond metal detectors and security cameras. Districts are now purchasing visitor management systems, weapons scanners, drones designed to stop attacks, AI systems that claim to identify weapons before they enter a building, and software that continuously monitors everything students type on school devices. Most of these tools have limited or no documentation on their effectiveness in making schools safe, and several have already led to damaging outcomes for students, including suspensions, expulsions, arrests, and wrongful police confrontations. AI systems have been at the center of some of these concerning incidents, including:

AI-Integrated Weapons Detection Systems. Some have sparked wrongful arrests of students in several states. One middle school in Florida was shut down and police dispatched to the scene after the surveillance system flagged the presence of a suspected weapon "being held in the position of a shouldered rifle," which, upon further review, turned out to be a clarinet. Another incident saw a Maryland high school student confronted at gunpoint and handcuffed by police after his school's AI detection system misidentified a bag of chips as a weapon. There is little to no empirical evidence that AI systems actually prevent shootings.

License Plate Readers. Some U.S. police departments search a national license plate reader database that includes data gathered from AI surveillance and school district security cameras to assist federal immigration enforcement. The practice raises serious concerns about whether school surveillance technology purchased for student safety is being repurposed to target students and families without school districts' knowledge or consent.

AI Monitoring of Students' School Accounts. Two federal lawsuits have been brought by students and parents in Arizona and Kansas challenging their school districts' use of Gaggle, an AI platform that continually monitors students' school-issued accounts, violating their privacy rights. In one of these lawsuits, plaintiffs claim the software deleted student photography and artwork after incorrectly flagging them as indecent. Both lawsuits allege violations of students' constitutional rights.

What Works in School Safety

As school, district, and state leaders confront growing concerns about student safety, these technologies can appear to offer simple, tangible solutions. Yet mounting evidence raises serious concerns about their impacts, while research demonstrating their effectiveness remains limited. As investments in unproven safety technologies continue to grow, it is critical that leaders understand the potential harms these tools can pose to school communities and instead prioritize research-backed strategies to improve school safety.

What works? The evidence behind various school safety approaches is compelling. Overwhelmingly, it indicates that the best way to keep students safe in schools is not just to attend to students' physical safety, but to ensure their psychological sense of safety as well. This means focusing on evidence-based strategies, including the following:

• Build Trusting Relationships. Positive, stable relationships between students and school staff can help prevent physical violence and bullying. A major national study of more than 36,000 secondary students found that school connectedness reduced the rates of school absenteeism, substance abuse, and violence. Research also shows that positive relationships significantly enhanced the odds of students communicating potential threats to adults. Notably, student bystanders who came forward with knowledge of a threat were more likely to have a trusting relationship with one or more adults in the school.
• Create Positive School Climates. Successful violence prevention strategies include the use of comprehensive school safety plans grounded in providing environments where students feel a strong sense of belonging. The National Institute of Justice's school safety framework names school climate as one of three core components for effectively preventing school violence. A research synthesis found compelling evidence linking a positive school climate to school safety, highlighting increased feelings of connectedness and positive perceptions of physical and emotional safety among students, as well as decreased negative behaviors, including aggression and violence.
• Provide Mental Health Supports in Schools. Effective school counselors can reduce disciplinary incidents and disciplinary recidivism and improve students' academic achievement and teachers' perceptions of school climate and student behavior, especially for boys. However, schools' ability to provide the needed support is strained. On average, public schools have only one counselor for every 372 students and only one school psychologist for every 1,071 students. Just under half of all schools offer mental health treatment services.
• Implement Restorative Practices and Programs. Such programs consistently improve school safety, reduce the use of exclusionary discipline, decrease rates of student misbehavior, and improve school climate. High rates of student exposure to restorative practices at school also increased achievement and reduced mental health challenges. While 60% of schools reported using some form of restorative practices in 2019–20, studies confirm implementation challenges that require more intensive investments in professional development.

Every dollar spent on school safety is ultimately a choice about what kind of environment schools create for young people. Districts can invest in technologies that monitor and sometimes criminalize students, but these measures often come with significant psychological costs for the school community. Instead, districts should make informed investments in school security while maintaining a focus on the relationships, supports, and school climates that research consistently shows keep students safe. As resources, time, and capacity continue to be limited, it is critical to make decisions based on the evidence, and the evidence indicates that when schools invest in approaches to improve psychological safety, physical safety follows.