Until last year I had been a school psychologist for 23 years. School safety, in the form of metal detectors, surveilance cameras, on-site police officers, etc. may have its place. Additionally, teaching about bullying, diversity, tolerance and coping strategies to students and teachers, is also important. However, these compensatory efforts are usually developed to treat the symptoms, or behaviors that are secondary to other personal and/or societal issues.
Implementing the strategies mentioned above only work to make things better if the implementation is thorough and follow-up occurs. To present a new strategy at a faculty meeting and then expect all teachers to buy into it and carry it out is almost completely ineffectual, but due to financial constraints and overwhelming time constraints and demands on teachers and other school personnel this is often what happens.
Implementing safety strategies are difficult at best. To post a sign on all the doors, which states that all visitors must report to the office, and requiring all teachers to wear nametags, again is ineffectual. In a school where teachers have been told to redirect strangers back to the office I have repeatedly witnessed unknown persons without visitor passes passing school staff easily. The secretaries in the office are often too busy to even notice people entering the building. Visitor passes are easily obtained and, while visitors are supposed to sign in and sign out, it is a simple task to leave the building with the pass, which could then be used by someone else. Going through a metal detector does no good if someone outside is willing to pass a gun through a window. Again, the point here is that schools are trying to create safer environments, but with so many other priorities imposed on them (e.g. SOLs, No Child Left Behind, IEPs, bus duties, breakfasts, lunches, and paperwork for everthing they do) safety is one more straw on a struggling camel's back.
Behavior in school is usually an extension of behaviors out of school. Developing in-school strategies and devices, while providing some improvement, is not the complete answer. At least not the long-term answer. Schools are one institution in our society. A child's school is one component in her or his life that may also be filled with chaos at home, neglect, poor nutrition, physical or sexual abuse, societal prejudice, family mental and/or physical illness, witnessing spousal abuse, homelessness, drug manufacturing in their home, drug use and various addictions, poor communication with their parents, along with society's inability to provide appropriate intervention for these problems.
While schools are indeed the one institution through which almost all people pass, and would be the perfect place for screening, triage, referrals to community agencies, etc., without the ideology, without the mandate, without the funds, these things cannot happen.