The new Teacher Development Trust (TDT) CPD Landscape Report 2025 offers a revealing snapshot of professional learning across England. It shows that while schools are investing more time and money in CPD, much of that effort still isn’t translating into meaningful classroom change.
More than a third of teachers said CPD had not clearly improved their ability to perform their role, and fewer than half described it as relevant to their day-to-day practice. The activities with the greatest reported impact, such as coaching and teacher collaboration remain used by only a small proportion of schools.
It’s a familiar paradox. The evidence about what makes professional development effective is stronger than ever. Yet the provision remains patchy. If we know what works, why is it still so hard to make it happen?
In this special guest blog, Andy Newell, Founder and Managing Director of IRIS Connect explores how meaningful teacher professional learning – or Didagogy – must reach beyond the mechanics of training programmes to include the cultures and forums that allow teachers to reflect, share challenges, and collaborate in solving the problems of practice.
We know what works, but implementation is the challenge.
The evidence is clear and consistent. Professional development is one of the most impactful and cost effective levers available to school leaders. An evidence review by the Education Policy Institute (2020) found that high quality professional development had a clear positive impact on both pupil outcomes and teacher retention.
Across 52 randomised trials, the average effect on pupil attainment was around 0.09 standard deviations, a gain similar to the difference between a novice teacher and one with a decade of experience. High quality PD also improved retention, particularly for early career teachers, helping to reduce dropout during the first few years of teaching.
We are also gaining a sharper picture of what counts as high quality PD. Coaching, for example, is increasingly recognised as a key component. Kraft and Blazar’s study (2018), which showed an impact on pupil achievement of 0.18, has influenced much of the CPD landscape in recent years. The growing evidence base, however, is clear that coaching alone is not enough. Other learning interactions and cultural conditions need to support it. Visscher et al.’s latest meta-analysis of the impact of PD programmes (2025) identified three additional factors which play a key role.
- Clear cognitive and behavioural modelling. i.e. supporting teachers to understand the “what and the why” of the change
- Building reflective skills so teachers can better understand their practice and the steps needed to improve
- Cultural conditions and mechanisms that enable teachers to provide each other with feedback and share knowledge and skills
This work echoes the work of Kraft and Papay (2014) which showed that teachers in supportive professional environments i.e. strong collegial relationships, effective leadership, meaningful feedback, and a culture that valued learning, improved nearly 40 percent more over ten years than those who did not.
Introducing a coaching programme “out of the box” can appear easy, but building and sustaining a broader professional learning culture that values reflection and collaboration can be more challenging. This is why The TDT’s recent work to differentiate the professional development of teachers, Didagogy, is so welcome as it brings a renewed spotlight on the specific cultural, practical and professional challenges of teacher professional development.
Didagogy: teaching teachers as professionals
Teaching is demanding in ways few other professions can match. It calls for deep subject knowledge, strong pedagogical understanding, careful planning, and fluid technique, all coordinated by the ability to notice and respond to learners’ needs in real time. Balancing these procedural and responsive demands requires the situational awareness and professional judgement of the adaptive expert.
Developing adaptive expertise sets a high bar for professional development. It involves striking a careful balance between activities that build knowledge and automaticity, and the mental models of practice that underpin noticing and judgement. Any system that privileges one over the others, or sequences them poorly, risks creating a mismatch between the nature of expertise it develops and the demands of the role.
For instance, if a programme pays insufficient attention to building the automaticity of key routines, teachers may experience excessive cognitive load as they consciously deliberate over every instructional move. In such cases, situational awareness becomes crowded out by other concerns. Conversely, if a programme emphasises behavioural rehearsal at the expense of dialogue, reflection, and collaborative sense-making, it risks cultivating habits untempered by reflection, leaving teachers less able to adapt to change or identify opportunities for growth and undermining the collaborative culture of learning that will support growth beyond the training room.
This challenge is compounded by the realities of the profession. Unlike musicians or athletes (domains which were studied by Anders Ericson as he developed his definition of deliberate practice) teachers do not have extended rehearsal time before performing. There is simply not enough time to train formally for every complex situation or dilemma they will face. For this reason, professional learning must reach beyond the mechanics of training programmes to include the cultures and forums that allow teachers to reflect, share challenges, and collaborate in solving the problems of practice.
Of course, all of this has to be sustained within the constraints of limited resources, staff turnover, and the politics of schools. By recognising the distinctive nature of this work, the Teacher Development Trust plays an important role. Through its reframing to Didagogy, it acknowledges the complexity of the challenge and provides space for informed discussion and collaboration. Crucially, by drawing attention to the novelty of the task, it helps guard against the one dimensional quick fixes, often imported from other fields, which may appear attractive, but frequently overlook the complexity and nuance of teaching.
About the Author:
Andy Newell, Founder and Managing Director of IRIS Connect.
IRIS Connect supports schools to overcome barriers of time, location, and capacity to achieve sustainable improvements in teaching. Their innovative PD platform is driven by adaptive development pathways, practical technique guides, classroom video observation, and AI-assisted lesson insights to enable adaptive instructional coaching, guided self-reflection, and seamless collaboration within and across organisations.
