My job sometimes takes some explaining at parties. “You choose to work with teenagers?” people ask “Wait, those teenagers?!” Such incredulous responses are typical. I look over my glass at the sceptical thirtysomethings - who might be working in publishing or graphic design or for a charity - with far fewer grey hairs than me. But for the grace of God, I could be one of them…

I once imagined that I would leave the classroom after my first two years. Teacher training and placement programme Teach First’s marketing comes in for some flack. But for me, fresh out of university, the scheme’s try-before-you-buy approach to a career - getting paid for doing something that engaged with society while having the option to swing on out again at the other side with a load of new skills - appealed to me.

I chose to teach design and technology - an odd choice, having just finished studying history, but I’d loved it at A level, so why not? On my first day, in my new suit, surrounded by 12-year-olds with tenon saws, it seemed like it had been a really smart idea. But appearances can be deceptive.

As those first few weeks and months flew by, I found that I really did love my job in the technology department. But a lot of my classes were more boisterous than those of my other Teach First colleagues. It dawned on me that BTEC construction, business and technology classes were full of pupils who weren’t expected to excel in triple science or my beloved history. Typically behind their peers academically, my pupils also displayed what my Teach First tutor called “challenging behaviour”. But I quickly became aware that I enjoyed working with them the most. For one thing, I often found them witty and creative, and capable of pulling a fast one on me on more than one occasion.

One such time in those heady Teach First days I was practising a new technique of “praise in public; chastise in private”. Following some minor disruptive behaviour, I attempted to have a word with the pupil in question, outside of my classroom. Unseen by me, his friend followed me to the door and locked both of us out. After a few minutes of laughter, another student took pity on me and came to unlock the door. To my surprise, my relationship with the class improved.

Another time, I’d overslept, and got into class with only moments to spare. One of my students delightedly pointed out to me that I was wearing two odd shoes. If I had been a different type of teacher, perhaps I’d have been embarrassed or annoyed. But I always found myself seeing the same funny side, as the kids did. And with all of these experiences came the realisation that revealing my own vulnerabilities occasionally made my students feel safe in my class. They started to drop their defences and pick up tools.

I soon realised that I wasn’t just a tech teacher. My most memorable class had the 10 lowest-performing pupils in the year - all boys, all with special educational needs and/or English as an additional language; they found themselves united in my construction class. To say they were difficult to teach would be an understatement.

But as our three-year BTEC unfolded and relationships grew, I learnt a lot. I started to read my students’ behaviour differently and to spot where sudden outbursts, difficult days and weeks were coming from.

At first, I might have thought that immaturity was the explanation for irrational aggression when it came time to write things up, or when a pupil’s project work went missing in the workshop.

Over time, I began to think more deeply about special educational needs and disabilities, and realise why some situations quickly became difficult for certain students. I spent time with the English department, working out how I could sneak literacy into my lessons and how to head off trouble before it began by spotting communication challenges.

And I learned that some of these pupils were not just having a tough time at school, but were also very vulnerable outside the gates. One boy regularly missed school due to complications in his home life. His project work was an important part of his week: it was the one place and time when he felt really successful, and he created something that impressed others. Early on, I realised that in my complicated crew, all my students were vulnerable to leaving at 16 with no qualifications. If they were to carry on feeling successful after school, I needed to up my game.

As I learned how to read my pupils better, I learned how to teach them better; my job was to teach them not just literacy or workshop skills, but also - importantly - how to interact with each other positively and to be aware of, and more in control of, their behaviour. That year, 100 per cent went on to college at 16.

I felt incredibly proud of Abdul, a boy who went on to train as an electrician. At the beginning of our course, he had not coped well when work didn’t turn out right. Now he had enough confidence with practical tasks to be willing to challenge himself in new ways.

I distinctly remember realising that success in my lessons had shaped how my students felt about themselves. And that, working together over three years, I had played a big part in helping them get the passport qualifications they were leaving school with. Feasibly, these two things would influence the course of their lives from this point onwards. What a privilege.

During this time, our department was changing. It is a Teach First cliché to run into a head of department (HoD) role before you can walk. But in my first year, our HoD was the one doing the walking - and not coming back. The school was rapidly changing, pulling out of special measures and heading towards a “good” rating.

After a year of watching Led Zeppelin videos at the front of the class while he was supposed to be teaching, and bribing pupils to scribble in books before the new regime of book-looks, our HoD decided the change he needed was not to come back after summer. (He just forgot to tell us.) When I arrived back in September, I looked left and right for the grown-up stepping forward to lead the department…before I realised it would be me.

It soon dawned on me that my new job outside the classroom was similar to the one I had within it: facilitate, be fallible, provide support and challenge, and believe in people’s ability to grow. Our team grew stronger. Student outcomes improved. Behaviour never stopped being challenging, but our responses to it became more skilful.

I had come a long way from that first intrepid day in my “temporary” teaching job. As two years turned into the best part of a decade, I became increasingly interested in development: taking on initial teacher training, whole-school teaching and learning; and finding myself loaned out to other schools to support their school improvement. I loved putting my experience into different contexts: retrofitting learning to a new situation and butting against the boundaries of my knowledge, to learn new things.

But when I stepped into a pupil referral unit (PRU), I worried that it was a leap too far.

PRUs are typically much smaller than other schools, serving about 50-100 pupils, and with much higher ratios of adults to pupils. Walking in on my first day, tasked with developing teaching and learning, it all felt very reminiscent of my first few weeks in the profession. As I faced children with needs that I didn’t understand, I felt totally deskilled. If I couldn’t control my class, how was I meant to help other teachers to develop?

But appearances can be deceptive. As the first phase of unfamiliarity abated, and as I watched and learned from the colleagues around me, I began to realise similarities between the PRU and my first department: children who have often been written off by adults in their lives, at home and at school; and teachers who haven’t always been given the attention and development they deserve to do their job.

Currently, less than 2 per cent of excluded pupils get their passport qualifications in English and maths. And recruitment difficulties mean excluded pupils are two-and-a-half times more likely to be taught by an unqualified teacher. A challenge, then, but one worth rising to.

My role in the PRU has been varied and has definitely pushed the boundaries of my practice. As well as doing familiar things - culture building, teacher coaching and development, initial teacher training for unqualified staff - I have also had to cope with totally new challenges.

Take diagnostic assessment: how do you set a baseline assessment for a learner who is alienated by school and hasn’t yet built relationships with new teachers, and has missed a lot of school and has gaps in their learning? Curriculum planning: can you design a scheme of work that allows new learners to join it throughout the term, as they get excluded? Classroom management: what seating plan works for eight students?

PRUs and alternative-provision schools are also places for existential pedagogy. But what is best to teach?

Whatever you decide for your curriculum, it will not directly build on what each student has learned previously and neither will it lead neatly into what they will learn next if they are successfully reintegrated into mainstream. But for most pupils excluded in England today, reintegration is unlikely. So what do you need to consider if a pupil will finish their education in the PRU setting? This unit you’re planning can’t be a one-off. It has to build skills the students will need for later - after school. What are those, exactly?

But I don’t just do my job just because I enjoy learning myself. I know why I’ve stayed in education: I love teaching. That privilege I felt taking the same small group of boys through their three-year construction course is echoed in every class in the PRU.

Once trust is built, the relationships and the depth of understanding of pupil need is so rewarding - really getting to know and to teach learners, often through the most turbulent times in their teenagehood; and through great relationships, having some influence on what they are when they emerge out of school and into adulthood. To lead in such schools is an even greater honour. What a privilege.

Will Moss is head of learning at The Difference

The Difference recruits mainstream leaders for two-year placements in a PRU senior leadership team, where they learn from colleagues’ expertise and share their own. After their placement, they return to mainstream schools and pass on the skills learnt to other staff, while supporting vulnerable learners before they reach the point of exclusion. The new charity also provides specialist training in the best pedagogy to improve literacy, positive post-16 destinations, pupil wellbeing and safety, and coaches Difference Leaders to translate this into strategic school improvement (accredited as an NPQSL). The Difference is inviting interested teachers to learn more at IncludEd, a free CPD conference for which Tes is media partner