As a substitute teacher these past four years, I have been in more classrooms in our two public high schools than I can count. And, aside from an occasional lock-down exercise and teacher-lounge stories of students acting out, I have always felt safe.

And why not? We have wonderful kids in our district who come from mostly solid backgrounds where respect is a cornerstone. Whatever teenage stressors some of our students face, those issues seem to be resolved regularly through meetings with counselors and the deans.

Then Chardon, Ohio, happens. A teenager opens fire on classmates for no immediately apparent reason, killing three and injuring two others. Suddenly, memories of Columbine, Colo., Virginia Tech and Northern Illinois University come rushing back. And I realize that no educational institution is completely immune.

What is worse is that I begin to wonder whether someone among the hundreds of seemingly innocent, happy students I see regularly may be feeling so angry, isolated or bullied to snap.

"Could something like this shooting happen here?" I ask myself.

The answer is yes.

Blogger Jenn Savege's powerful piece, "From Columbine to Chardon: Why We Must Never Forget," reminds us that, "We can honor the lives lost in the horrific school shooting by vowing to remember how and why these tragedies occur."

A reader added, "Of course, none of us want to live our lives in fear of a tragedy occurring at our child's school or anywhere else. But I think it is exactly when we stop thinking that these things can and do happen anywhere that we open ourselves up to tragedy.

Another of Savege's readers, "S. Thompson of Washington" noted that "as a nation, while we are shocked when these things happen, we don't necessarily draw the connection to our own communities. I think we've become accustomed to the `it didn't happen here so we're safe' mentality. It's scary if you think about it so the truth is -- we don't."

It was easy to leap to the conclusion that the Chardon shooter was isolated, bullied and pushed over the edge. But one young woman earlier this week noted that the 17-year-old suspect had always been there for her and was a good listener. He offered support and a shoulder to lean on.

Nevertheless, there will be much speculation how the shooting was planned an why particular students were shot. I'm not sure we'll ever know.

Savege pointed out that it has been 13 years since the at Columbine shootings brought discussions of bullying and school violence to the forefront. After Columbine, school programs were initiated to get guns out of schools, help minimize school bullying and open lines of communication between school administrators and the students who may be able to report unusual behavior before it's too late.

Our high schools have a strong and very active anti-bullying program and as it was getting underway late last year I had an opportunity to lead some discussions at Fairfield Warde. The discussions were eye openers and I was surprised to hear how many incidents of bullying these students had seen and had reported. That day was a reality check for me.

Further, I have the utmost respect for the school counselors in our two high schools and middle schools, where seeds of problems like Columbine's and Chardon's can begin to grow. I feel so much more comfortable when a student asks to go to his or her counselor. While those students rarely look distressed, they may have a clear need to talk that's more important than class time.

An administrator at the Chardon high school, trying to make sense of the tragedy, reminded us that Chardon could be anywhere and that no one is immune. These innocent students could have been anywhere in the United States, calmly eating breakfast before school began. But in a split second, lives were lost or shattered and other students faced their own mortality, looking for a safe haven or the loving arms of a parent.

Once again, we must not forget that this tragedy happened, and those of us who work with students should try to look even harder for the slightest behavioral change or quirk that could signal a Chardon brewing in our own backyard.

Steven Gaynes is a Fairfield writer, and his "In the Suburbs" appears each Friday. He can be reached at: steven.gaynes@yahoo.com.