The start of a teacher training year is full of excitement and challenge. For those entering the field of secondary computing, this excitement comes with an awareness that they are joining a subject area facing acute pressures. Computing remains a relatively new curriculum area, replacing ICT with a more rigorous focus on computer science, digital literacy, and information technology. Yet there are not enough qualified teachers to deliver this new vision. Last year, the Department for Education set a target of over 1,200 new computing teachers. Fewer than 500 trainees were recruited nationwide. That gap of over 800 represents classes of pupils who will not receive specialist teaching unless schools adapt and stretch existing staff.

Against this backdrop, the computing PGCE is both demanding and vital. Roehampton has seen its largest cohort to date this year, a sign that efforts to attract people with computing backgrounds into teaching are bearing fruit. These trainees bring diverse experiences: some have studied computer science at university, others come from industry or related subjects, while a few are switching careers entirely. What unites them is a willingness to learn how to teach computing well and to pass on a passion for the subject to their pupils.

Professional formation in this context involves two distinct strands. The first is subject knowledge. Computing is hard to teach without deep understanding. Programming, for example, cannot be approached in the same way as theory-only topics. A teacher must be able to demonstrate coding fluently, explain complex processes clearly, and anticipate the misconceptions pupils will have. While many trainees arrive with some programming experience, few are equally confident across all areas of the curriculum, such as networks, algorithms, and cybersecurity. Python is the main language used in schools, and trainees are encouraged to strengthen their skills early, both through independent study and peer support within the cohort.

The second strand is pedagogical knowledge—the craft of teaching. Much of this is best learned in school, through observation, practice, and reflection. Wednesday sessions at university introduce relevant research and provide opportunities for trainees to explore teaching strategies, but the richest learning takes place in the classroom. This is why the partnership between schools and the university is so critical. Mentors play a pivotal role, offering day-to-day guidance, modelling effective practice, and giving constructive feedback that helps trainees develop their own style.

A helpful way to picture this professional formation is through a Venn diagram. In one circle lies subject knowledge: computing itself. In another lies generic pedagogy: how to teach any subject. The overlap, known as pedagogical content knowledge, is where computing teachers learn how best to teach their specific subject. For example, managing behaviour in a computer lab presents unique challenges. Pupils often see computers as toys rather than learning tools. Establishing clear routines from the first lesson is essential, and mentors can help trainees by sharing strategies that work in their setting.

As well as technical skills and teaching craft, trainees must grow into the professional role of a teacher. This involves understanding the statutory framework within which schools operate, including safeguarding, professional conduct, and the need to uphold public trust. Teachers are held to high standards both inside and outside school. Something as simple as a lapse in punctuality or an ill-judged social media post can undermine confidence. Mentors are key in helping trainees navigate these expectations and model the professionalism required.

Assessment of trainees is structured around the Teachers’ Standards. By the end of the course, mentors must judge whether each trainee has met all eight standards to the level expected of a newly qualified teacher. This includes setting high expectations, promoting good progress, demonstrating secure subject knowledge, planning well-structured lessons, and managing behaviour effectively. Mentors observe lessons, provide formative feedback, and record evidence of progress. Importantly, they also identify areas where the trainee needs additional support and work with university tutors to address these.

The journey is not always smooth. Early in placement, trainees may struggle to gain attention or maintain order in the classroom. They may misjudge the pitch of a lesson or underestimate the time needed for pupils to grasp a new concept. This is normal and part of the learning process. What matters is that they are supported to reflect, adapt, and improve. Mentors can help by breaking down challenges into manageable steps, such as focusing on one behaviour strategy at a time or co-planning a lesson to address specific gaps in understanding.

The wider context for this work cannot be ignored. Computing is a gateway subject. Pupils who gain confidence in programming and computational thinking are better prepared for future study and employment in a digital world. Conversely, pupils who lack access to skilled teaching may be shut out of opportunities. The stakes are high, and so the responsibility shared by mentors and the university is significant. Together, they are shaping not only individual teachers but also the future of the subject.

Professional formation, then, is a collective endeavour. The university provides theory, research, and structured training. The school provides authentic classroom experience and the day-to-day realities of teaching. The mentor stands at the heart of this, bridging the two worlds and helping trainees translate abstract principles into concrete practice.

For mentors, the challenge is to see beyond the trainee’s current limitations and to nurture their potential. This involves patience, clear communication, and a willingness to reflect on one’s own practice. It also involves celebrating small successes: the first well-managed starter activity, the first pupil who finally understands a tricky concept, the moment when a trainee’s lesson flows smoothly from start to finish.

By investing in these new teachers, mentors are investing in the future of computing education. Every conversation, every piece of feedback, every modelled lesson contributes to a trainee’s growth. At a time when the subject faces a national shortage, the role of mentors has never been more important. Through their guidance, trainees become confident, capable teachers ready to inspire the next generation of digital creators.

Notes for mentors, based on the the first Roehampton PGCE Computing lecture of the year