When I was 16, I was put on what police call a "School Hit List". A student, one year younger than me, ranked and ordered 10 of us in terms of killing priority. I don't remember much more about that traumatizing time except that I was number 7 on that list and one of my favorite teachers was target no 1.

It's hard to believe that event had little bearing on my choice to enter the educational profession, but 15 years later (and in my 8th year as a teacher), I occasionally look out into the masses of current and former students and wonder – could something like that ever happen again? And, better yet, could it happen to me?

These thoughts and questions were dredged from the depths of my memory this week – two days, two teachers murdered.

The first of these tragedies occurred on Monday. Mr Michael Landsberry's is a story of heroism, as he lived a life of being "in the line of duty". While on recess duty, eyewitnesses reported gun shots rang out from a 9mm handgun, injuring two students. Most fled for safety, but Landsberry, an 8th grade math teacher, casually approached the shooter to reason with him. Minutes later, he was tragically shot. After serving his country in the armed forces for most of his life, he was gunned down by a 12-year-old boy on an outdoor basketball court at Sparks Middle School, Nevada.

Mr Landsberry is my hero; if something like that ever happened at the middle school I teach at – one not too different from his – I'd hope to have half the courage and composure he exhibited not just on that day, but for his profession, his students, and his ultimate sacrifice.

On Wednesday, Massachusetts experienced a similar loss. Ms Colleen Ritzer was allegedly murdered by a 14-year-old student in her last class of the day. This young man stabbed her to death in the school's bathroom with a box knife, dragged her body out of the school in a recycling bin, and dumped her remains in a nearby forest. According to the local CBS affiliate, Ritzer asked the boy to stay after class to talk about how he was struggling with his math.

Ms Ritzer's beaming smile seemed only to be overshadowed by her kindness towards students and her love of math. She was an avid Twitter user (@MsRitzerMath), and her tweets seem indicative of her fondness for her profession. One from 11 August is telling:

No matter what happens in life, be good to people. Being good to people is a wonderful legacy to leave behind. — Colleen Ritzer (@msritzermath) August 11, 2013

However, the big question remains: how many more teachers have to be slaughtered and slain, leaving behind a wonderful legacy before we take action? Cari Harris, a fellow teacher, said it best in a blog post on The Educator's Room:

Well, considering that teachers now face the danger of being killed while doing their jobs, perhaps it's time we focus a little more on how to support our educators in real and authentic ways.

In every community in the free world, we have one thing in common – schools serve as the epicenter. It's a place for our children, their growth, and our collective future. Schools help fashion and forge the next generation, and I – like surely Mr Landsberry and Ms Ritzer were – am proud to serve my community as a teacher. Our profession shoulders a vast responsibility, but a rewarding one.

As a teacher, I find it so difficult to think about the gun shots in the searing heat of Landsberry's Nevada playground and the struggle Ritzer faced in a faculty bathroom on a dark autumn evening in Massachusetts, but find it more difficult that most of the public has already moved on; ready for the next story. I could only imagine Mr Landsberry paid this same penitence as an active duty soldier, but he traded his weapons for a different set of tools – hope, awareness, encouragement, and education.

Building these tools in every teacher, every community, and every student, are perhaps the only way to make for a safe school that is destitute of hatred, violence, and Hit Lists. I certainly don't want any other teacher to ever ask themselves – could something like that ever happen again? And, better yet, could it happen to me or my students?

• This commentary was amended on 26 October 2013 to clarify that Michael Landsberry taught in Nevada and was killed on Monday.