Unfortunately, many school districts do not have a lot of money to provide adequate security.  In many other cases, money allotted for security is spent in a wasteful manner, leaving children and school staff at risk.

Many school districts spend a lot of money on emergency management, which is good. However, prevention (being proactive) is equally important. There are many techniques that can be implimented that are not very expensive.

In most schools, there is usually only one way in and that is usually through the main office. However, in many cases, office personnel are not properly trained and unable to stop someone determined to get in. And, the fencing usually is not that high, has two or more gates and is easily negotiated. 

Security officers are only as good as their training and the policies implimented allowing them the full benefit that the laws extend to them.  If not properly trained, especially those who are armed, it could create a greater risk rather than controlling or eliminating the incident.