When I showed up at the junior high in Queens that Halloween morning, I was the fourth English teacher most of my students had seen that school year. There was no reason for them to trust me. The girls were starting to figure out how the world worked, for better or worse, and most of them had some idea what they wanted to be when they grew up. The boys, on the other hand, were chaos.

They were thirteen and fourteen, moderately taller than I was, solid with muscle. They loved the Mets or the Yankees, and often dressed in Knicks and Rangers jerseys. They had vague, implausible plans for their futures. They were a bristling, nervy pack, with mediocre attention spans torn between their female classmates, the movement of light outside the classroom, and opportunities to prove their masculinity. They were horny and rank, on the threshold of becoming men.

I, twenty years older, had recently arrived on that same threshold. Like them, I was dealing with a sensory blur, strange new crops of hair, unpredictable arousal. My skin hurt all the time, and my bones moved and flexed, trying to grow. I stopped at every mirror to see whether my facial hair had sprouted. My voice was changing, and when I raised it to quiet the kids, the result was usually cracked and squeaky.

At first, I had no idea how to be a man or a teacher. The principal assigned me to a senior teacher who thought I was a butch lesbian the first few times he saw me. I had never been a butch anything, so this was a puzzle. I liked him, but the endless jokes about k. d. lang and strap-ons made me claustrophobic and wary. When I eventually confirmed my trans-ness for him, he wanted to know what kind of penis I had, and what my name had been. But he also helped me navigate the complicated maze of gender, culture, and religion at our particular junior high school.

I came to New York for the usual reasons: romance, adventure, reinvention. When I applied to the NYC Teaching Fellows program, I was a woman. When they accepted me the first time, I turned them down, pretty sure that transitioning in front of the classroom would be a disaster. When they asked the second time, they knew about the transition, and I figured that if they were cool with it, I would go ahead and try. I thought that by the time I got to a classroom in November I would be done, or at least done enough.

What I didn't know was that I would never be done. Even racing through the steps of transition, straying from the regimented pathway that governs most transitions, I hardly passed as male when I started my teacher training. My first day with the Board of Ed that September involved carrying my name change documents and a letter from my surgeon to each of the gatekeepers, trying to convince them that I was a man so they would change my paperwork. I nodded and smiled, pushing through their resistance with Bambi eyes and my sheaf of paper. In my training group, nobody knew what I was, so my classmates called me "he" or "she" interchangeably.

As a student teacher, I wore a jacket and tie every day, but I was still too short, and my feet were too small. My mentor teachers didn't know what kind of woman I was, but they agreed that I was no kind of man. Using the staff men's room was a trial that required me to show my manly new driver's license to the security desk every time. When student teaching ended and I went to a job fair at the end of October, the junior high school's assistant principal liked me. She said I seemed kind of maternal, which she thought would help the students. She didn't know that sometimes I missed being Ms., instead of Mister, because when I was Ms. Posey, a teacher aide in Chicagoland, I could nurture the kids. I was pretty sure that Mr. Posey couldn't nurture, that a certain standard of hands-off masculinity would have to be achieved.

Over the course of that first year in Queens, my feet exploded from men's seven to ten and a half. I was hungry all the time, and when I ate I found myself tearing at my food, wolfing it like the boys did in the cafeteria, trying to get enough. Dubious whiskers began the slow creep up my jaw and upper lip, but refused to conform into sideburns. My voice settled down. Meanwhile, I tried to keep my classroom together, surrounded by young men and women whose bodies were as combustible as mine.

Adolescents want to know everything about their teachers, but they don't like to think about the details. My kids were no different. They watched me change. Sometimes they commented on it. Every now and then I would catch them looking at me as if they could almost see who I had once been, or who I was trying to stop being. They made a lot of hobbit jokes, especially as they got taller and I, falling off pace with them for once, did not.

There were also kids who watched Maury or Jerry Springer, who had seen men like me on their TV screens. One of them tagged a desk in my classroom: POSEY IS A TRAVESTITE. I panicked, started to make a scene, pulled myself together. By the end of the day, I was more annoyed by the misspelling than by the threat of exposure.

By the end of the year, I'd helped students through pregnancy scares and problems with their parents, the disappointments of the NYC specialty high school application process, and a bewildering array of standardized tests. I had also taught them about books and language, and the tools that words could be. Meanwhile, my assistant principal told the kids that I was a Navy veteran (I am not), and so they expected me to be strong. They said arm-wrestling was manly and so of course I accepted their challenges, even though I knew there was no way I'd win. I wanted the rush of contest. I didn't want to embarrass myself, but in the end I was no match for those boys. I made a mental note to think about going to the gym, and went back to talking about books.

The school year went on. We all grew up. As I looked more like a regular man, I realized that I cared much less than I had about what everyone thought I was. Passing was a luxury that I was no longer sure I wanted. By the end of that year, I was out to some of the other faculty. My mentor colleague expressed his concern that people would try to collect me, make me their token trans person, if I outed myself much more. I didn't want to be collected, but I also didn't want to hide.

When I was a very young lesbian, I had a bumper sticker on my car with Audre Lorde's immortal quote: "Your silence will not protect you." My mother used to argue that silence was absolute protection, that hiding somehow equaled survival. For me, though, it was the opposite. I believed ACT UP when they said that silence = death. I believed Lorde when she said that silence was not safety. For the most part, it's harder to hate a group if you know people who are part of that group. When colleagues took time to get to know me, I made a point of coming out. In my apartment, after all, there were no secrets. I'd kept pictures of me as Small Girl, and my past was not especially distant. With colleagues to whom I had little or no connection, I let gossip take care of the situation and decided I didn't mind what they knew or what they thought. When they liked me, I was glad, but I didn't especially care when they shunned me.

Looking back, I believe that going through my second puberty while my students were going through their first lent me insights that most teachers are denied. The girls appreciated my calmness about their periods, and the boys valued my empathy for their fractured attention. The last of my secondary students have finished high school now, and many of them have gone to college. Many of them are out and proud as queer. At least one has transitioned. At the end of my third year in NYC schools, having transferred to a high school in Brooklyn, I'd become the faculty advisor for the GSA. I wore a rainbow bracelet; it was hard to figure out how to be out as trans, so I relaxed into letting everyone think I was gay. Because this was also true, it felt, most of the time, like a reasonable compromise.

Visibility is important, and my resume has more trans on it than I ever would have expected, but being visible at a secondary school is harder than being visible at a college, or on the lecture circuit. Although I never go into class and announce myself as trans, it's out there on the internet, in my list of publications. Many of my former students found me on Facebook or Twitter after graduation. I often post trans items on social media, and sometimes they click like. They also search out links they think I will like, and ask me to comment on their writing. Their interest, and the occasional note of appreciation for my teaching, makes that baffling first year feel like a success – everything I learned helped me be more effective at the high school and college levels. I don't know how it would go, if I started over in secondary schools again, but sometimes I would like nothing more than to find out. I miss being the go-to guy for the queer kids and misfits. And I miss being the teacher who teaches his kids about their power…even when it means I have to arm-wrestle.