I can’t say that I am an “irreplaceable” teacher. But I do know that some of the teachers that I have worked with are, and that we have chosen to forsake our school.

The education policy group TNTP coined that term this summer in a report that calls for changes to teacher retention policies. The top 20 percent of teachers are “irreplaceables,” TNTP concluded, and yet they must be replaced far too often. Like many educators, I may take issue with some of the flashpoints of TNTP’s report — the aggrandizing term of “irreplaceable,” the focus on firing “low performers,” the notion of merit pay, or the idea that the wheat can even be separated from the chaff given the measures that currently exist.

But I think the report called attention to an important conversation that needs to happen about retention. It’s well past due that we focused on the toxic cultures and conditions in public schools that cause capable teachers to leave.

The report got one critical point right: most teachers depart due to a failure in school leadership. As the report further notes (under “low-cost retention strategies”), the remedy for this failure can be heartrendingly easy: All it would often take to retain some effective teachers is a few positive words of recognition. Beyond this simple remedy, most teacher-leaders furthermore crave the opportunity and support to work with other teachers and school leaders to best meet the needs of their students.

Being a principal is a lonely gig. You have to resist the human urge to gossip and confide in staff. You have to consistently follow through on your words. You have to be humble enough to sit back and let others problem-solve and take credit for solutions, even when you’ve set up the systems and structures to guide them through the process. You have to be an active listener, and make decisive choices. And probably the toughest part of it all is that no matter how thoughtful those choices are, you will still be criticized behind your back by staff, and little appreciated for your hard work.

I’ll be the first to say that the role of school leader is a thankless job. But for better or worse, a position of leadership is one of responsibility. If quality teachers are departing for other schools year after year, then the onus is squarely on school leadership.

TNTP’s advice to principals is to focus on supporting and encouraging successful teaching practices, while making it clear that ineffective teaching practices will not be tolerated. I believe this is sound advice. The result is a culture of high expectations that values good teachers.

In the struggling school I have chosen to leave, that dynamic was oddly reversed. It seemed, at times, as if the most involved — and, most likely, effective — teachers were the ones most ignored, or even in some cases critiqued and alienated. I could provide many examples of such treatment of teacher-leaders, but my purpose here is not to air dirty laundry. Let it suffice to say that the common theme threaded through many of the stories of teachers who attempted to go above and beyond is that they were all too often censured, rather than supported. The end result was that instead of teachers working together with one another and with the administration to solve problems and provide the best service possible to struggling students, staff and teachers worked in relative isolation, spoke up rarely, and unfortunately sometimes even stabbed one another in the back in the struggle to garner favor with school leadership.

I suppose it is possible that you can be an effective teacher to the students in your classroom, and not be very involved in the larger school community. In fact, in the school that I left, such non-involvement could be viewed as a necessary recourse for long-term survival. There were a few battle hardened veterans who went into their classrooms, shut the door, and did their best for their students, quietly abstaining from involvement in the political dimensions of the workplace that could place their well-being in jeopardy. I believe such grim survivalism is the reality in many public schools across this nation. But I also believe that this is ultimately detrimental to the school as a community and to the student body as a whole.

I want to be clear about one aspect of that struggling school: It is not struggling because teachers were ineffective or incompetent. In fact, in that school there lies dormant a vast human, social, and even physical capital entirely untapped, and that is what is the greatest of crimes. The staff and teachers are ready and willing to give it their best, but they require a strong and clear vision and organizational systems to steer them. The students face tremendous challenges, but they are willing to work to their potential with the assistance of systematic academic interventions and emotional and social support. There is a library full of wonderful books, rarely used. There is a music closet full of instruments, rarely used. There are classroom closets stuffed with programs from bygone years, no longer utilized. The wealth is there, largely squandered. Let this be an allegory for our public school system at large.

One of the many involved and effective teachers in that school was effective by any measure, test scores or otherwise. She never took a lunch to herself; her students were in the classroom with her, reading and writing. She was there after school, planning lessons, reading papers, tidying up. She was there on the weekends, working unpaid to tutor students. Students would wait for her outside her door every morning. They couldn’t get enough of her, because she kept asking them for more. She was relentless and firm, kind and caring. She established mentoring relationships with all the students she came across, not just her own. She talked about leadership, believing in yourself, working hard, giving it your all, and she modeled what she taught every single day, in and out of the classroom. When I think of an “irreplaceable” teacher, I think of her.

And yet, she was treated so poorly by school leadership that despite her wholehearted dedication to that community and to her students, she chose to leave and go elsewhere. She was rarely praised. Her efforts to go above and beyond for her students — such as conducting fundraising for field trips — were inexplicably stifled, rather than supported and encouraged. And all she wanted was to do the best she could for the students in the school, many of whom rarely had opportunities to go on field trips or be exposed to an enriching curriculum. And she was not the only one.

The reason for this treatment? I can’t be sure, though I certainly have my theories. I have heard enough from colleagues in similar situations at other schools to conclude that it can’t simply be ascribed to one or two inflexible people, but instead to a toxic school culture. And changing that culture, on the part of school leadership, is relatively easy: just a few simple words of recognition in place of silence, passive aggressiveness, or outright hostility would go a long, long way.

It wasn’t the working conditions that caused myself, and other teachers to leave, although the conditions were unpleasant. The school’s 120-something-year-old building showed its years (a deluge of water burst through my ceiling my first year and wrecked my social studies books); schedules that changed so frequently that you would walk in each day expecting it to change; students that ran and yelled out in the hallways; teachers and school leaders engaged in vicious gossip; meetings that materialized out of thin air without any advance notice; messages blared over the PA system in the middle of each and every lesson … I could go on and on.

Again, it wasn’t these conditions that caused us to desert a community we had invested so much of ourselves into. Teachers everywhere deal with these sorts of issues — and far worse — every day. We left because school leaders failed to establish a culture that would support and value involved, effective teachers. In that school, as President Obama encountered in D.C., politics trumps problem-solving. When politics takes precedence over effectively meeting the needs of students, such a corrosive school environment becomes untenable.

This week, I am starting to teach and serve as special education coordinator in a school where a community of high performance and professionalism is valued. I don’t regret any of the time I served at my former school. It was a profound learning experience, and I will miss the staff and students that I worked with greatly. But I will not regret leaving.

About our First Person series:

First Person is where Chalkbeat features personal essays by educators, students, parents, and others trying to improve public education. Read our submission guidelines here.