Professor Charles Hulme is a man on a mission: to get the education sector to recognise the importance of language skills in learning and, relatedly, the often-overlooked prevalence of language difficulties in the youngest students.

Throughout his career, including in the role he has just retired from - professor of psychology and education in the Department of Education at the University of Oxford - Hulme has pioneered research into the development of reading, language and memory processes. He is also an expert in the use of randomised controlled trials in education to evaluate interventions.

From 2004, along with fellow Oxford professor of psychology Maggie Snowling, he led the development of the Nuffield Early Language Intervention (NELI) programme.

The result was an evidence-based oral language intervention for children in nursery and Reception who show weakness in spoken language skills and are at risk of experiencing difficulty with reading. Such was the success of the programme that, in 2021, the government confirmed funding to offer it to all state primary schools in England, with a particular emphasis on schools in areas of social deprivation.

In September 2023, the Education Endowment Foundation (EEF) published its final evaluation of the national roll-out of NELI, which found that four- and five-year-olds who received the intervention made an additional four months’ progress in language skills, while those eligible for free school meals benefited from a seven-month boost to their language skills.

We caught up with Hulme for a conversation about the impact of the programme, as well as his findings on the crucial importance of early language development, what the risks can be for students who struggle in this area and what staff should know about the interventions that help.

Do you think that there is currently enough awareness in schools about problems associated with language development?

I would say that language impairment is massively under-recognised. If you say to most people, “Do you know about dyslexia?”, they will say, “Oh yes, dyslexic children have problems learning to read”. And if you ask, “Do you know about autism?”, they will say, “Oh yes, I know all about autism, my neighbour’s got a child who’s got autism spectrum disorder”. And then: “Do you know about language impairment?” They’ll say: “No, I’ve never heard of that.”

So I’m on a crusade to persuade people in education to recognise the central importance of language. For instance, developmental language disorder, or DLD, is every bit as common as dyslexia and autism, but so few people seem to know about it.

The best estimates are that somewhere between seven and 10 per cent of the general population have clinically significant language difficulties.

Why do you think there is so little recognition of DLD?

At the moment, there isn’t enough written or broadcast about it, which is a factor. Plus there’s the fact that, in the classroom, these children often blend into the background.

A five-year-old may be quiet, not misbehaving and not causing any trouble for the teacher. He may actually understand almost nothing of what is being said to him, but he can see what other children are doing and, if the class is told to do something, he’ll be able to copy others, so he seems to be working well. But he’s not really understanding what’s being said.

What is known about the causes of DLD?

These problems reflect both environmental and genetic influences. There’s good evidence that language problems are, to some degree, heritable, which means that they’re under genetic control, but everything is partly genetic.

The development of language problems reflects something called gene-environment correlation. Children whose parents have poor language skills pass on poor genes for language learning, and they also probably provide them with a poor language learning environment. So these children have got a double whammy. That’s why school is so important, because these kids really need help in school to compensate for problems in the home environment.

There’s also a strong gradient relating social class to language ability. Our University of Oxford spin-out company, OxEd and Assessment, has been funded for the past four years to provide NELI free of charge to schools in England, and we’ve got a massive data set of more than half a million children who have been assessed with our LanguageScreen app.

We’ve found that there is an 11 standard score point difference in the language skills of children in the most deprived schools compared with the least deprived schools. It’s a huge effect. So the kids in the most deprived schools, as measured by the proportion of children in receipt of free school meals, have much poorer language skills than the children in the least deprived schools.

What do we know about the impact this can have on those young people’s education?

Language is the foundation for the whole of education. It’s the foundation for learning to read and write and spell. But it’s also the medium of instruction. The whole of education involves people speaking to you and giving you information, so if you don’t understand what’s being said to you, and if you can’t express your understanding to people, you can’t do anything in education.

But it’s surprisingly hard to get people in education to understand this, partly because there’s such an obsession with the teaching of phonics. People have to realise that there’s more to reading than phonics and there’s more to comprehension than decoding. And that’s very much concerned with language.

There’s also good evidence that language problems are highly associated with problems in psycho-social development, and we know kids with language problems are less happy. They’re more likely to have so-called internalising disorders - like depression and anxiety - and are also more likely to have so-called externalising disorders, which manifest in being “naughty”, acting out and so on. And then they’re likely to have lower educational attainment, lower occupational success, and possibly psychological and emotional problems in adulthood.

So, language problems potentially have massive effects on every aspect of your life.

Do you think people are beginning to recognise this? For instance, Labour has made ‘oracy’ a cornerstone of its plans for education, should it be elected, and the shadow education secretary, Bridget Phillipson, has stressed the importance of focusing on language and communication, particularly in the early years.

I do think that the critical role of oral language skills for education and for social relationships and wellbeing more broadly is gradually being recognised by education professionals and by politicians. This can only be a good thing.

How does NELI help to support language development?

The programme is based on traditional thinking about how to facilitate language development, so in that sense there’s nothing revolutionary about it.

What’s different is putting it into the hands of mainstream educators - in particular, that it is designed to be delivered by teaching assistants (TAs). We provide thorough and expert online training, which upskills these people and enables them to do a great job in facilitating the language development of children in the school.

What we’re trying to do is take language difficulties away from being a specialist problem, where you have to get a speech and language therapist into the school to work with a child intensively. That is great, but the resources don’t really exist to do that.

So we’re trying to make language work an integral part of mainstream education, with a particular emphasis on targeting the children who are struggling with language and who will benefit most from getting the help.

How does the programme work?

It’s aimed at Reception kids - roughly between four-and-a-half and five-and-a-half - but during lockdown, many schools carried on using it in Year 1. The children who will take part are identified with our LanguageScreen app, which is an automated app that can assess speaking and listening skills in 10 minutes, giving an accurate assessment of the child’s language level. Those found to be requiring help are given three small group and two individual sessions a week with the TA.

In those sessions, there’s a lot of talking and the children are taught vocabulary explicitly. They’re listening to stories, having conversations about stories and being asked to retell them. They’re looking at pictures that represent simple stories and being asked to tell the story.

If the child gives a very limited response, staff are trained to use a technique called scaffolding to take what the child has said and expand it, and get the child to repeat that expansion. So, if the child sees a picture of a boy chasing a dog, for example, and says, “Boy; dog,” they’d say, “Yes, that’s right. The boy is chasing the dog. Can you say that?”

One of the critical things in the success of our programme is getting children to produce language in a supportive environment and have that language scaffolded by the person working with them to make it more complete or more extensive.

Another aspect of the programme is that there’s a big emphasis on teaching children to listen. They are taught to pay attention to language, and also to speak when they’re asked to speak, but not to blurt out answers when they shouldn’t.

One of the impressive results we got in our last, very large, randomised trial was that the children who had the NELI programme were found by teachers to have improved behaviour, become more attentive, less disruptive and more sociable than the kids who hadn’t.

Do you know what’s happening for those young people?

I think we’re producing broader metacognitive changes. We’re taking kids who find language difficult and teaching them that, actually, they can learn language and engage with it, and that they need to ask people when they don’t understand things. We’re changing their attitudes to learning language, I would say.

Working at things and mastering things that are difficult gives you a different attitude to learning, and turns you into a more active and purposeful learner. And we’re doing that quite early in children’s lives. We’ve shown in the latest data, which isn’t published yet, that these improvements in language persist for at least two years after the programme’s finished, which, again, is a huge result.

Some teachers have pointed out that NELI is time-consuming and that freeing up TAs to deliver the intervention is difficult when staffing and budgets are already stretched. What would you say to them?

The NELI programme does involve significant amounts of TA time, but I think this investment of time is justified because the programme is proven to produce appreciable and durable improvements in children’s language skills.

Ideally, though, schools should receive funding to increase the availability of TAs to support the valuable work they do with NELI, and the other roles they play.

Some people have also raised concerns that NELI is limited to four- and five-year-olds. However, you are now launching a new NELI pre-school programme. How does that work?

It’s important to emphasise that it’s a different programme. It’s for kids in nursery or pre-school, so from three-and-a-half to four-and-a-half - the year before they enter formal education.

It’s a whole-class language enrichment programme, built around repeated reading of a set of early reading books. It’s basically 20 to 30 minutes a day, for the whole class, in mat time with the teacher, reading a story and then teaching vocabulary and doing a set of exercises around the story. And that’s coupled with small-group and individual support for the five or six children in each class who most need it, identified through LanguageScreen. These children get more work to reinforce what’s happening in the whole-group sessions.

We have just published the randomised control trial on this and we’ve got strong results. We’ve shown that the whole-group programme raises the language levels of all the children in the classes receiving it by quite a substantial amount, and also raises the language levels of the kids who are getting the targeted help on top of the whole-class programme.

The fact that we can get improvement in the language ability of the whole class, with something that the teachers and the kids like, I think that’s pretty startling and really important.

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