Reggie says that he has not seen his teacher for three days. It’s not strictly true. He’s definitely seen his teacher, but he has been spending a lot of time outside of the classroom. And when he is in the classroom, he doesn’t actually have that much interaction with her.

So when he says he hasn’t seen his teacher, what seven-year-old Reggie really means is that he has not been taught by her. To him, though, it amounts to the same thing.

Reggie has been spending most of his time with Ms Wrightson doing small-group activities. Ms Wrightson is the class teaching assistant. She’s in charge of “Red” group.

Reggie was put in Red group within a few days of returning to school after the summer break. He didn’t really know why he was put in that group, but he knows school is now different from how it was before Covid. And he’s not sure whether he likes it.

There were thousands of children like Reggie in schools in the autumn. In all phases of schooling, all across the UK, pupils who had been left behind the rest of their peers because of the lockdown were grouped together by senior leadership teams who had decided that intense catch-up sessions with TAs were the only answer.

It’s a strategy with a lot going for it. However, it’s not without its drawbacks. Because while certain pupils, in certain contexts, with certain interventions, can progress well as a result of these TA-led sessions, they are not a magic bullet solution for Covid catch-up.

Indeed, there is a real danger that in urgently trying to close gaps, schools will fall head-first into the “intervention trap” and possibly make things worse.

The research on TA interventions

On the face of it, TA-run intervention groups make perfect sense, and there is good evidence to show that, when done well, they work well. Very well.

What does “done well” look like? Largely, we are talking about structured interventions that are clearly planned out, have explicit protocols to adhere to and that may have some scripted elements. We’re also mainly talking about time away from the normal run of the lesson, rather than a TA providing extra scaffolding in-class around a task every other pupil is working through at the same time. And in terms of the research, we are largely talking about specific numeracy and literacy interventions (see box, below).

For example, a group of children struggling with phonics may work with a TA in a small group in timetabled slots, away from the main class teaching. They may work through a structured phonics intervention over a set number of weeks.

Or in secondary, it might mean a small group of Year 7s taking part in a targeted numeracy intervention over a six-week period, shortly after transition, so that they are able to fully access the secondary maths curriculum.

The evidence for the effectiveness of that basic framework of intervention is incredibly and consistently positive. And that effect has been found in both US and UK studies.

If you search the 100-plus Education Endowment Foundation-funded trials of classroom approaches, you’ll find there are 12 different trials of TA-led interventions, from the early years up to Year 7, and 10 of those show a positive impact. Pupils made, on average, between two and three months’ additional progress compared with those in a “business as usual” condition.

Considering that trials of a range of education innovations funded by the EEF and its equivalent in the USA, the Institute of Education Sciences, show that despite the best possible conditions, around 80 per cent do not return a positive impact on learning, what we see in relation to TA-led interventions is genuinely remarkable. While certainly no cure for educational underachievement, it does represent the kind of marginal gain that school leaders should seize on.

So we have as near a conclusive verdict as we’re likely to get to the argument over whether a TA-led intervention can have a positive impact: the answer is yes. The real issue is how do you make sure it has an impact? How do you get those returns.

And that’s where that intervention trap starts to loom in front of you.

There will be a very understandable and sensible reaction from schools when they start seeing where the gaps are, how big the gaps are and with which groups of children those gaps are greatest. They will move to invest as quickly as possible in a programme of interventions to be delivered by teaching assistants for exactly the reasons stated above: it’s cost-effective, it means that the teacher can keep the majority of pupils on track and, above all, there’s thumping good evidence for its effectiveness.

But then the problems begin. And they look like this.

Trap 1: TA-led intervention as a catch-all

Mixed into your attainment data, hiding in the graphs and numbers, will be pastoral concerns: some pupils will have fallen behind, and will still be struggling, for emotional reasons. Unfortunately, TA-led interventions around wellbeing have a much weaker evidence base than academic interventions.

Schools need to be really careful. They need to thoroughly ascertain the specific challenges that each pupil faces. Because if the barrier to learning is an emotional one, then the expectations that they will have for any TA-led intervention - even one that is well-evidenced as having a positive impact - are going to be too high.

Wellbeing interventions designed to be delivered by TAs cannot unpick complex emotional challenges. And TAs cannot work miracles academically if the emotional side is the main challenge. Expecting them to do so isn’t going to do them or the pupils any good.

There will be pupils with needs that require a specific type of emotional support - perhaps from an external agency. It’s essential that schools seek out the right support for those pupils before, not instead of, any academic intervention.

Trap 2: The TA-only option

Once you have properly addressed pastoral concerns, it would be natural to group together the children who have fallen the furthest behind, to plan your roster of interventions, and to start assigning TA staff. Natural, but not necessarily right.

Leaders will need to take a moment to consider what form of intervention each child actually needs. Because for some pupils, a full TA-led structured intervention is going to be overkill. It might be that some teacher input on a small-group level is enough. The only way you are going to know is by giving it time. How do pupils respond to teacher-led scaffolding? Is it enough? You can’t make assumptions. Children always surprise you.

But even if pupils don’t respond, is it necessary that the intervention be TA-led?

We need to disrupt the pattern that intervention is when a TA takes a certain number of children out of class and completes a structured programme on a specific academic area. Yes, there is evidence that works, but it doesn’t mean you always have to do it that way.

Indeed, while there is evidence that TA-led interventions lead to pupils making progress, there is also evidence that if teachers lead those interventions then pupils make even greater progress. So if the gap really is that extensive, then is there not a case for the teacher to lead the intervention or to at least deliver some of the sessions?

It’s worth bearing in mind that evidence additionally shows that volunteer-led interventions tend to be less successful than ones delivered by TAs. So if you are expanding your staffing to include volunteers, it is essential that you think about which staff teach which pupils and which groups.

If we over-rely on TAs and/or volunteers, it flies in the face of everything that we know we need to do to avoid compounding the effect of missed learning time for the pupils most disadvantaged by time away from school. If your furthest-behind children are steadily making progress, but their peers - thanks to their teacher - are making even more, that gap is not going to close.

During the planning phase, it might be worth considering the deployment of one or two teaching assistants as “intervention specialists” fully dedicated to the delivery of catch-up programmes.

Consider some of the advantages: the role may suit - and optimise the knowledge and skills of - TAs with a background or degree-level qualification in a literacy or numeracy-related subject; specialists become experts in a small number of carefully selected programmes; practice is more consistent; and teachers would have a single point of contact for planning and discussing pupil progress (see box, below).

Trap 3: The teacher offload

If the TA is to lead the intervention, how involved should the teacher be? The research suggests that the answer should be “very”. Does this always happen? Unfortunately, the answer is no.

TA-led interventions can go into overdrive as national examinations, such as Sats or the Phonics Screening Check, draw near. The interventions are familiar, the teacher spots the children in need of a boost, and off they go. The teacher’s involvement tails off and she/he is essentially replaced with a TA.

Instead, the teacher needs to be fully involved so that the intervention can be tracked, evaluated and tweaked for individual children. Teachers need to be across the detail: where are the gaps and which specific things does each child need to practise in order to close the gaps? Also, how are those gaps closing as the intervention progresses, and how will intervention work feed back into the normal run of classroom work?

That last point is crucial. The evidence suggests that you get an extra shot of impact on pupil progress when teachers and TAs make explicit and practical connections between interventions and the work that’s happening in the classroom.

As a simple example, if the intervention group has been working on a particular phonics blend, it really helps if adults give those children opportunities to practise that blend in the context of classroom learning later that day.

What’s more, those connections are crucial for another reason: it can help you get a proper overview of the child’s experience. If a teacher is involved in planning the intervention and then connecting that to the work in class, they can immediately see to what extent the intervention work is impacting on the child’s wider development.

It can also help teachers to avoid putting pupils on a carousel of interventions that, like Reggie in our introduction, keeps them out of class for extended parts of the week.

Speaking to a head a couple of years ago, I asked him to list his interventions: he reeled off more than 20.

Suddenly he recognised the problem: “I’ve got kids coming out of interventions to go into other interventions.” His teachers had lost sight of how pupils were progressing. He was horrified.

Trap 4: Square interventions, round pupils

Have you got the right intervention for the pupil, or is it just the best programme that you have available?

A common issue is where a teaching assistant has training in a certain intervention and the school then tries to match the needs of its pupils to that intervention.

It’s understandable: training is expensive, the TA is time-poor, and you want children to catch up quickly, so you haven’t got time to send the TA on another course (which, in any case, may not be available because of Covid).

And yet the evidence is clear that you only get impact from well-targeted interventions delivered by well-trained TAs. If you’re going to take pupils out of lessons, a minimum expectation is that what they receive at least compensates for the time away from their teacher. Be mindful about what you’re willing to compromise on.

The other prerequisite is making sure that the interventions you choose are properly and independently evidenced. There are a lot of poorly evidenced options out there - do your homework or you could well waste time and money (see box, below).

Trap 5: Social exclusion

Do you think about what a child misses when they are in an intervention group?

For a start, just like Reggie, they miss relationship-building time with a teacher. A 2013 study I led found that primary-aged pupils with statements (now education, health and care plans) spent the equivalent of a day a week away from the classroom. Compared with their peers, the relationship that pupils with SEND have with their teacher can be weaker as a result.

We all know that relationships matter hugely to academic outcomes, so make sure you mitigate against the effect of time out on teacher-pupil relationships.

And what about friendship groups? Every time a pupil is pulled into an intervention, you disrupt friendship groups. As well as potentially creating resentment, the peer support group that you relocate them to may be less effective than the one you remove them from.

Consider this: your school runs an intervention for young children with speech and language difficulties. The TA works heroically on developing their communication skills. Yet the one thing they miss is, by definition, the one thing they won’t get from those sessions: excellent modelling of speech and language from other pupils. In trying to help the intervention group, we deny them a valuable source of assistance.

It is worth looking at the composition of groups and how interventions can work differently for at least some of the time.

And be careful of another form of resentment that may be simmering away. Which lessons are pupils pulled from? In our research, we have seen, for example, that if you take the sports-mad child out of PE - a subject they excel in - to do extra maths week after week, you are unlikely to be catching them in a mood where they’re receptive to learning. It’s not much fun for the TA either. Again, ask yourself: is time spent in an intervention compensating for time away from mainstream lessons?

Trap 6: Well, we could shift…

It’s an awkward thing to raise, but sometimes a school’s commitment to an intervention is not as rock solid as it claims it to be.

Many TAs I’ve spoken to say that it’s not uncommon for intervention sessions to be hijacked. They could be on their way to collect their first group of the day when they are spotted by a member of SLT, who redeploys them to Year 3 to cover a staff absence. The result? Intervention sessions for maybe a dozen struggling pupils get bumped, yet again.

Why does this matter? For a start, consider the message that sends to those children: we’re essentially saying, “Your reading really, really matters, but just not today.” Don’t underestimate the knock-on effect that could have on a child’s motivation.

Secondly, as the evidence shows, well-run intervention programmes are tightly structured - and you must stick to that structure if you are to get the most out of it.

Fidelity - that is, doing exactly what it says on the tin - is what gets results. Programmes have strict conditions for working, such as how long you do it or even the number of children who should participate. The temptation now may be to have larger groups, as more children will be in need of the intervention. Resist tinkering with protocols, or you won’t get the impact that the evidence promises.

The right time

None of the above is a comment on the value or contribution of TAs - they are an essential part of the school and of a pupil’s learning journey. None of this is an argument against TA-led interventions - the evidence is clear that, in the right circumstances, they work.

What the above does attempt to do, however, is urge caution.

The deployment of teaching assistants to lead interventions is tailor-made for the situation that we find ourselves in: helping children left behind after a long lay-off from the classroom. But we should be thinking of TAs as a pivotal part of a broader, coordinated catch-up strategy. It’s a big responsibility that will require a substantial amount of thought and a considered approach that steers schools away from the numerous traps that could trip them up. We can’t afford to trip up - we need to get this right first time.

Rob Webster is associate professor at the Centre for Inclusive Education, UCL Institute of Education, and a lecturer at the University of Reading. He created the award-winning Maximising the Impact of Teaching Assistants programme

This article originally appeared in the 11 September 2020 issue under the headline “Beware the intervention trap”