Nova: Imagine spending over four billion pounds a year on something in schools, only to discover it might actually be holding students back. That's the startling reality the Education Endowment Foundation uncovered about teaching assistants in England.

Nova: That's exactly what the landmark DISS project found back in 2009, led by Peter Blatchford and his team at UCL Institute of Education. The largest study of its kind, tracking over 8,200 pupils across seven year groups — and the results were genuinely shocking. Sixteen out of twenty-one findings went in the wrong direction. The pupils who received the most teaching assistant support actually made less progress than similar pupils who received little or none.

Nova: That tension is at the heart of the EEF's guidance report, Making Best Use of Teaching Assistants. Originally published in 2015 by Jonathan Sharples, Rob Webster, and Peter Blatchford, and then updated in 2025, it tackles this uncomfortable question head-on. And here's the hopeful part — it's not that TAs can't make a difference. Under the right conditions, they can add three to four months of additional progress. The problem is deployment, not the people.

Nova: And I'm Nova. Let's get into it.

Nova: To understand why this guidance report exists at all, we need to go back to the study that changed everything — the Deployment and Impact of Support Staff project, or DISS. Conducted between 2003 and 2008, it was the largest and most rigorous investigation into how TAs were being used in UK schools.

Nova: The researchers tracked two cohorts of pupils across seven age groups, measuring progress in English, maths, and science. They controlled for prior attainment, special educational needs, free school meal eligibility — all the factors you'd expect to influence results. And the pattern was stark. Pupils with the highest levels of SEN, who typically receive the most TA support, showed the most pronounced negative effects.

Nova: Exactly. And it gets more specific. The research showed that TAs tended to be task-focused rather than learning-focused. Their interactions with pupils often closed down discussions about the learning content. Instead of helping children think through a problem, TAs would guide them toward completing the worksheet.

Nova: Peter Blatchford, one of the report's authors, has described how TAs were effectively becoming an informal teaching resource for the lowest-attaining pupils. Not through any bad intent — schools were trying to help. But the effect was that these children spent less time with the qualified teacher, more time separated from their peers, and their learning suffered.

Nova: And the spending reflects that: approximately 4.4 billion pounds every year. The DISS findings essentially asked: is this 4.4 billion pound investment delivering returns, or is it inadvertently widening gaps? That question set the stage for the EEF guidance report.

Nova: The original 2015 guidance report made seven recommendations, later streamlined to five in the 2025 update. But they all orbit around three big ideas: deployment, practice, and preparedness.

Nova: The report describes what's often called the Velcro TA model — where a TA is assigned to a specific pupil, typically one with SEN or low attainment, for long periods. They sit next to that child, lesson after lesson, and effectively become that child's primary educator.

Nova: Precisely. The first recommendation — and it's deliberately provocative — says TAs should not be used as an informal teaching resource for low-attaining pupils. The guidance is crystal clear: the pupils who struggle most should spend at least as much time with the teacher as other pupils, if not more.

Nova: And the report argues this has to stop. Teachers must retain responsibility for all pupils. The TA should add value to what the teacher does, not replace them. This means breaking away from the one-to-one TA-pupil assignment model and thinking more strategically about how the whole teaching team works together.

Nova: The updated 2025 guidance gives some practical examples. A TA might supervise peer reading fluency practice, where pupils learn from each other. Or they might pre-teach concepts, vocabulary, or skills before a lesson so that pupils arrive better prepared. Another option: the teacher splits the class into two groups, the TA supervises one group through a teacher-prepared task, and the teacher works intensively with the other group.

Nova: The second big theme in the guidance is about the quality of TA-pupil interactions. The DISS research had observed that TAs often prioritised task completion over learning. The guidance tackles this through the concept of scaffolding.

Nova: The 2025 report describes scaffolding as giving pupils the skills and tools to help themselves in situations when they do not know what to do. The key word there is help themselves. The goal is increasing independence, not creating dependency.

Nova: Exactly. The guidance outlines different levels of scaffolding, from most to least intensive. At the highest level, you have correcting — where the TA directly points out an error. Then comes modelling, where the TA demonstrates how to approach the task. After that, clueing — giving hints but not answers. Then prompting, which is more open-ended. And finally, self-scaffolding — the pupil has internalised the strategies and can apply them independently.

Nova: Yes, and this is where the third recommendation gets really practical. The guidance says TAs need to have what it calls the essential need-to-knows before every lesson: the concepts, facts, and information being taught; the skills to be practised; the intended learning outcomes; and the expected feedback they should give.

Nova: That's sadly common. The report acknowledges this and suggests creative solutions: adjusting TA working hours so they start earlier or finish earlier, using assembly time for briefing, even having TAs join teachers for part of their planning, preparation, and assessment time. The point is, you can't expect TAs to scaffold learning effectively if they don't know what the learning is meant to be.

Nova: Here's where the story takes a genuinely hopeful turn. While the evidence on everyday TA classroom support is sobering, the research on TAs delivering structured interventions tells a completely different story.

Nova: The EEF's Teaching and Learning Toolkit shows that when TAs deliver high-quality, structured interventions in one-to-one or small group settings, the impact is roughly three to four additional months of progress. That's an effect size of about 0.2 to 0.3 — modest but meaningful.

Nova: The guidance identifies several common features. First, the sessions tend to be brief — twenty to fifty minutes — but they happen regularly, three to five times a week, and are maintained over a sustained period of eight to twenty weeks. Second, TAs receive extensive training, typically five to thirty hours from experienced trainers. Third, the intervention has structured resources and lesson plans with clear objectives.

Nova: Precisely. The guidance also stresses that assessments should be used to identify the right pupils, guide the areas of focus, and track progress. Effective interventions ensure the right support reaches the right child. And crucially — and this is the seventh original recommendation, later woven into the 2025 update — connections must be made between what happens in the intervention and what happens in the classroom.

Nova: Exactly. The guidance says we should not assume pupils can identify and make sense of these links on their own. Teachers and TAs need to explicitly connect the dots. And the 2025 update adds a really important emphasis: interventions should be monitored for impact, using a two-fold approach — tracking progress towards learning objectives, and monitoring the quality of delivery. It's not enough to just run an intervention; you have to check it's actually working.

Nova: Let's talk about the evolution of this guidance, because the 2025 update is significant. The original 2015 report had seven recommendations. The 2025 version has five. But it's less about dropping ideas and more about consolidation.

Nova: The biggest shift is in tone. The 2015 report opened with a fairly stark message: the typical use of TAs is not leading to improvements. The 2025 report begins by acknowledging that TAs are crucial to the work of schools and colleges, and that their contributions are invaluable, particularly for pupils with SEND. It's a more appreciative framing.

Nova: There was definitely some backlash. But the 2025 report also broadens the training recommendation. Originally, recommendation four was about ensuring TAs are fully prepared. Now it says prepare and train staff around effective TA deployment — it's not just on TAs to get ready, it's on everyone, including school leaders and teachers.

Nova: Yes, recommendation five: engage all staff in the process of implementing effective TA deployment. The evidence suggests that if someone outside the senior leadership team is tasked with enacting change, it either doesn't happen or doesn't stick. A named senior leader needs to own this. The guidance also highlights the problem of role creep — the gradual expansion of TA responsibilities until they're doing things far beyond what they were hired for, often covering whole lessons or running informal inclusion units.

Nova: And the 2025 report acknowledges these challenges while staying focused on its core message: deploy TAs to supplement, not replace, high-quality teaching. The scaffolding recommendation now explicitly references metacognition. And there's a stronger emphasis on clarity — making sure everyone in the school, from the headteacher to the newest TA, can answer the question: what is the role of the TA in our school?

Nova: Now, Sage, there's an interesting connection here that many educators miss. The EEF guidance report talks a lot about the quality of TA talk — about avoiding interactions that close down thinking and instead using talk to stimulate learning. This is where the work of Robin Alexander comes in.

Nova: Exactly, and it's an important distinction. Robin Alexander is Professor Emeritus at the University of Cambridge, and his life's work has been about the power of classroom talk. His book A Dialogic Teaching Companion, published in 2020, argues that talk is not just a medium for teaching — it is teaching. And his research has shown that when teachers and support staff use dialogue effectively, children make significantly more progress.

Nova: Alexander's research identified that much classroom talk follows what he calls the recitation script — teacher asks a closed question, pupil gives a brief answer, teacher evaluates it. Sound familiar?

Nova: And Alexander's dialogic teaching framework offers an alternative. It's about asking questions that provoke thought rather than just test recall. It's about giving pupils time to respond — wait time, he calls it. It's about building on what pupils say rather than just judging it. The EEF even funded a randomised control trial of Alexander's dialogic teaching approach with 5,000 students in Birmingham, Bradford, and Leeds, and it showed positive results.

Nova: That's the sweet spot. And it aligns perfectly with the guidance's scaffolding framework — moving from correcting to modelling to clueing to prompting to self-scaffolding. Each level requires a different kind of talk. A TA who masters dialogic techniques can judge when to give a hint versus when to ask a question that nudges the child toward the answer themselves.

Nova: So let's get concrete. If you're a school leader listening to this and thinking, we need to rethink our TA deployment, where do you start?

Nova: Absolutely. The guidance recommends taking at least two terms to plan, develop, and pilot strategies on a small scale before rolling out across the whole school. And the first step is an audit. The EEF provides a Red Amber Green self-assessment tool where schools can rate their current practice against each recommendation.

Nova: Exactly. Then there's a TA observation schedule you can use to collect real data on how TAs are currently being deployed in classrooms. The Maximising TAs website has free templates for all of this. Once you've got a clear picture, you define your vision — what does great TA deployment look like in our school? — and create an action plan.

Nova: The report also includes a TA policy template. And the 2025 update is very clear that a named member of the senior leadership team must own this process. Without senior leadership driving it, changes won't stick. The guidance also highlights that SENCos — Special Educational Needs Coordinators — should be centrally involved, given their role in coordinating TA work.

Nova: That's the number one barrier schools report, and the guidance doesn't pretend it's easy. But it offers creative solutions: adjusting TA contracts so they start earlier or finish earlier to create briefing windows, using assembly time, having TAs join teachers for part of PPA time. Some schools have restructured their timetables so that TAs have dedicated preparation time built into their week. It requires investment, but compared to the 4.4 billion already being spent, the marginal cost of getting deployment right is tiny relative to the potential gains.

Nova: We've covered a lot of ground, so let's pull it together. The core message of Making Best Use of Teaching Assistants, the EEF guidance report by Sharples, Blatchford, and Webster, is this: when deployed poorly, TAs can inadvertently widen the attainment gap. But when deployed well — as part of a strategic whole-school approach — they can add months of additional progress, especially for the most vulnerable learners.

Nova: What's striking is that none of this requires hiring more people or spending more money. It's about redeploying the enormous resource schools already have — 260,000 TAs and 4.4 billion pounds a year — in smarter, more evidence-informed ways.

Nova: The evidence is clear. The tools are freely available. The question is whether schools have the courage to audit their current practice honestly and make the changes that the research demands.

Nova: This is Aibrary. Congratulations on your growth!