Anne Heavey hated school so much that she dropped out when she was 13, and it took the local authority two years to find out. She did her GCSEs in a year at the local pupil referral unit, and a year later successfully applied to Oxford.

“I think they like a wild card,” she says, with a grin. “The guy who wrote my reference was like: ‘You want to meet this one. She’s mad.’”

Whatever images “wild card” might conjure up, the Whole School SEND national director doesn’t fit.

We’re sharing a giant sofa cushion in the foyer of the hipster building where their offices are located. Two mugs of green tea perch uneasily on a four-legged sofa tray. We’ve coincided with free cupcakes day and there’s even (hallelujah) a gluten-free option. I’m settling in.

But while I’m surreptitiously slipping off my shoes and tucking up my feet, Heavey sits tall, poised – ready to be grilled. Her hair is pulled back; her glasses (bought online; “You really must try it,” she enthuses) emphasise the thoughtful air with which she ponders my questions.

“What intrigues me is how many youngsters whose primary need is physical are not in mainstream schools,” she says. “And I think we need to look at, you know, why haven’t we prioritised getting the school estate accessible?

“They could be progressing in line with their peers, or exceeding their peers… I think deciding what that minimum expectation is of accessibility is a conversation we should really have.”

You want to meet this one. She’s mad.

Heavey grew up as a young carer, and she speaks with an air of calm authority. “SEND was kind of my bread and butter,” she responds, matter-of-factly, when I ask how she got into the field. She’s aware that as well as financial barriers to schools adapting their environment to pupils, there’s also a confidence problem. “I think some aspects of physical disability can be quite intimidating, around medical care… Intimate care, feeding tubes and things. But it’s possible.”

Teacher discomfort pervaded Heavey’s childhood. As well as being lumbered with low expectations, “because, look at my parents”, teacher interactions could be excruciating. “My mum’s got quite complex disabilities. Her speech is affected as well, and it was very clear to me that people treated my parents differently to how they treated other people’s. At parents’ evening: ‘Hello… Mrs… Heavey…’ And she would sort of say: “You can speak at normal pace; it’s fine.” There was kind of a very patronising attitude.”

At primary school, Heavey “played up to” teacher perceptions of her as not very bright, to hide the real reasons behind her failure to complete homework: “Because I had other things to do at home. And I needed to keep that quiet.” But come secondary: “It all kind of fell apart because I wasn’t really able to manage fooling 14 teachers, when I’d only had to fool one.”

She spent years 9 and 10 teaching herself the piano and “reading everything”. “But being at home, I could help my mum out. So, you know, it worked.”

So how come no one noticed? “I was on a music scholarship at a private school,” says Heavey, “and their standards around keeping kids in are sometimes a bit different, so they just allowed me to leave.”

At the start of year 11, a neighbour got in touch with the local authority. “She was like: ‘There’s a kid round the corner that I don’t think is going to school,’” she says, wryly amused by her own story.

“Then the local PRU got in touch and said: ‘We’d like to invite you in and just have a chat,’ and then the most incredible people I’ve ever met in my life got me back in love with learning. I took six GCSEs in year 11, having not been to school since year 8.

“My tutor, Wendy, she was amazing. I just had three hours’ tuition a week. I popped into a local secondary school who helped with subject-specific stuff after school. Got me used to going into school again, and then we had a chat about, you know, what next.”

What next was a local sixth form. As a total music nerd – “I can’t remember them all now,” she says, “but I used to know the opus numbers for all the Beethoven piano sonatas and the keys… I was a proper loser” – music A-level was a natural choice. Her grandmother, whom she describes as “the original SEND mum”, bought her a cello when she was four. “They were like: ‘What do you want?’ And I was like: ‘I want that one,’” she jokes, mimicking Matt Lucas from Little Britain. “It was too big for me and my feet didn’t touch the floor, but there’s a picture of me holding this cello.”

She also took English, history and drama, “because I was shy and needed to learn how to be around people. Needed to re-humanise.”

Unsurprisingly, she wasn’t academically confident. “I thought, maybe I’ll get some Cs. Then my results came in and the head of sixth form said: ‘You’re going to apply to Oxford or Cambridge, right?’ He was amazing.

“They told me: ‘Just go for it. There’s literally nothing to lose.’”

She put in an application to Oxford to study music, and had to audition on the piano, which she prepared for “with the most patient music teacher who I think has ever existed… Because I arrived and was like: ‘Not done a GCSE, not done theory. Taught myself.’ I had some piano grades from back before I dropped out of school. We did grade eight in a year.”

She manages to be self-denigrating even in telling me that she was accepted. “I think they thought: ‘Disabled parents? Free school meals? Rural Nottingham? Yes, sure, babes.’”

Heavey loved Oxford – the tutorial system suited her aversion to big classes – and after graduating trained as a teacher. “Which given how much I hated school, I think is fascinating. But I did also leave teaching, so…” she trails off, with a cheeky smile.

She admits having been inspired by her tutors, particularly at the PRU, but also the A-level teachers “who took this complete basket case and just let me run. So I wanted to be that safety net for other kids”.

She left to join the Association of Teachers and Lecturers as policy advisor for curriculum, assessment and SEND – and in line the with union’s policy, she thinks more arts subjects should be included in the first-tier EBacc subjects. “They’re brutally hard, and really enriching. We learned about German history and the French Revolution through music, which I wouldn’t have learned elsewhere. I think I’d like to see that broadened out. I’m completely biased, and I’ll own that bias.”

Disabled parents? Free school meals? Rural Nottingham? Yes, sure, babes.

In June she was appointed head of Whole School SEND, a charity run through the National Association of Special Educational Needs that has previously received a government grant to develop a SEND audit for schools, and is now embarking on an even more ambitious project, the “SEND index”. In conjunction with University College London, which conceived the project, they are using surveys, Department for Education releases and Ofsted reports to document the state and condition of SEND provision in each local area – in order to identify pockets of excellence, and where to target support.

So what prompted her to apply for the role? “SEND is the thing that fires me up, really, and it runs very deep, and I just thought: “I’ve got nothing to lose by going for this. Things are changing at the NEU. Maybe it’s the right moment to move on.” It’s just that thing about empowering teachers to see the individual child, and who they could be, and help them on that journey. That’s what this project’s about.”