“Either he goes, or I’m taking my daughter out of the school.”

This is what a parent told me in confidence last summer. They were referring to a boy with Down’s syndrome, and associated behavioural difficulties, who had been in their daughter’s class for the six years of primary school. The boy was demonstrating behaviours that would see another child excluded. This included hitting, kicking, biting (students and staff), damaging property, swearing and disrupting lessons to the point that the classroom had to be evacuated several times a week – and their daughter was struggling to cope with the disorder.

We are an inclusive school, and were committed to meeting his needs, determined not to fail him. Special educational needs (SEN) experts had been involved from the start and full-time, one-to-one support was in place. Educational psychologists suggested a child-centred programme of study; speech and language therapists delivered communication therapy; occupational therapists designed programmes of activities to be done three times a day, requiring designated space and costly equipment. We accommodated all of this and more in our one-form entry primary school where both space and cash are at a premium, driven by his parents’ unwavering insistence that mainstream school was the only place he could ever reach his full potential. Other children with similar needs had succeeded here – why not him?

But in striving for inclusive education, we had unwittingly turned a blind eye to the elephant in the room. If inclusion requires a child to be excluded from the same experiences and boundaries as everyone else just to remain on the premises, then it’s not inclusion. I’ve lost count of the number of times I’ve been told to put the child first, but why only the child with SEN? What about the 29 other children whose education is hindered and – in some cases – personal safety jeopardised? I am responsible for those children too.

I am for inclusion, but not at all costs. In this case, the cost was not only the child’s happiness and progress, but the happiness and progress of everyone else in the school. We lost two good members of staff after they had been reduced to tears on numerous occasions by feelings of utter helplessness. On bad days, senior leaders would take over, trying every trick in the book but managing little more than babysitting to give staff respite and minimise collateral damage.

We had hoped that things would improve with more time and strategies. But as the child got bigger, more independent, physically stronger and emotionally aware, it was apparent we couldn’t offer the right help. We ran out of options.

Thankfully, the boy is now in specialist provision and, with the right support, is doing much better. But it was too late for some of his classmates who transferred schools to ensure their own education could proceed more effectively.

I recall the headteacher explaining that our school “believed in inclusion” and that we wanted our students to grow up understanding and tolerant of differences, prepared for the “real world”. But that’s not what was happening. In the real world, nobody would force someone with SEN to stay in an environment where they were coping so badly. The rest of the children in his class may well now have a negative view of people with Down’s syndrome, unfairly tainted by one experience.

Most primary teachers receive very little training in how to teach SEN students and it is often left to teaching assistants, who are even less qualified, to provide the necessary support. I remember his parents saying: “You can’t just put any learning support assistant with him, he needs a specialist with expertise in his area of need.” I completely agreed, but such specialists aren’t common and those with the skills the child needed tend to work in special schools, not as support assistants in mainstream primaries.

In year 2 we have a little girl with autism. She is doing well, but is prone to outbursts and sometimes lies down and refuses to move – it’s her way of coping. Her classmates have learned not to react to this and if she lies down they simply walk round her so lessons can continue. This is, in some ways, a positive thing: they accept her and don’t bat an eyelid when her behaviour is unusual. However, I can’t help but feel we’ve brought up a cohort of children who, when they see someone with special needs in distress, would assume they should just walk by without offering help.

Inclusion in principle is the right sentiment but, at best, it can come at a high price and, at worst, it can be a complete injustice. Children are individuals so the solution needs to be individual. There are plenty of examples of children with SEN who are successfully integrated in mainstream schools to the benefit of themselves and their peers. But if we want children with SEN to have the same opportunities to succeed as others, we should not feel guilty about admitting they may need a different environment in which to do this. Furthermore, our responsibility is to all children equally, not just those with SEN.

We need to be very careful that well-meaning ideals are not depriving children of their right to the specialist provision they need, nor indeed – if we are being truly inclusive – depriving others in the process. Inclusion, yes, but not at any cost.

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