ST. LOUIS - Some have suggested more metal detectors in schools might help prevent kids from bringing guns to school.

NewsChannel 5 checked with several large area school districts, and only the Saint Louis Public School system has metal detectors in middle and high schools. But we spoke with an expert in school safety who led the crisis response team after the school shooting that left 15 dead in Columbine, Colo.

Rick Kaufman is now a school security expert in the Bloomington, Minn. public school system. He says the best money is spent on intervention and prevention programs that teach kids to value and respect life.

"The best outcome today was this individual was caught," said Kaufman. "Someone had the foresight and the presence of mind to come forward. Because what we do know, is that in almost every one of these incidents the students tell someone about what they're going to do or have indicated in some way, shape or form that they wish to bring harm on someone else. When students and others that hear this bring that forward then we can act and we can react."

We also asked Kaufman about the timing of all this. He says the time just before winter break can be a trigger for some students, and pointed to the shooting at a school in Colorado last week, and the one year anniversary of the Sandy Hook shooting passed over the weekend. Kaufman says a number of factors play into why students bring guns into schools, and the approaching holidays can be one of them.

"So what we see is the two times of the year we see this," said Kaufman. "This is one of them. We're moving into the holiday break the holiday season is one where people where people are dealing with emotional issues, this becomes a very emotional time for them. They may not be dealing well with emotional issues. The other is the end of school."

Kaufman says schools are safe places to be and school shootings have actually declined since Columbine in 1999.