Even in the womb, his mother knew this was a baby to reckon with. He would kick her “nearly to death” for hours at a time. After he was born, he would cry for what seemed like hours on end. As a toddler, his tantrums made the normal Terrible Two’s melodramas looked like good-natured comedies. He wouldn’t, couldn’t, sit still for more than a few minutes and he always seemed hungry - for action, for excitement, for attention. The family was dominated by this tiny, howling whirling dervish.

Imagine his first foray into school. His teacher did try, but with 27 others to look after, it soon proved impossible. After a few weeks, the school arranged for him to attend two days a week with a helper and the rest of the time to go to a Pupil Referral Unit. This was done in opposition to a psychiatrist’s recommendation to put him into a residential psychiatric unit - at the age of five.

Unhappy with the PRU, his parents took him to a child psychologist who ran a battery of lengthy tests, having to follow him around the room on his constant wanderings. In the end, she diagnosed Attention Deficit Hyperactivity Disorder (ADHD), referred him to a paediatrician and, within two weeks, he was on medication and transformed. Soon after he started taking Ritalin, his mother received her first cuddle from him.

Now he’s back at school full time. When he comes home, he wants to sit and read his books.

Sean’s story is an extreme example of an ADD child (ADD is the generic term that covers both the hyperactiveimpulsive disorder and the similar but distinct inattentive brand). Few children with this newly-recognised disorder will display such exaggerated symptoms, nor will they require medication. But it is a good illustration of how a child can be misunderstood and misdiagnosed.

Educational psychologist Jenny Lyon, who specialises in ADD and related problems, says teachers and educational psychologists have told her how ADD is not acknowledged in their authorities. It’s not surprising when there is little training available.

East Sussex and Hampshire stand out in having set up ADD policies, but they are the exception. Overall, the numbers who are identified as having ADD are small but significant: between 3 and 8 per cent of children in the US, where it is accepted as a neurological, often inherited, disorder, and here - where it is seen as a psycho-social syndrome - 1 per cent. These are the diagnosed children.

Specialists say that they are only the tip of the iceberg. There’s no doubt in Jenny Lyon’s mind that many are simply seen by schools as bad children. Some are wrongly given statements of special educational need for emotional and behavioural difficulties and sent off to special schools. Others are sent to PRUs.

Naughtiness isn’t synonymous with ADD, she warns, although it can be a by-product of it. Teachers need awareness, through training, of what to look out for. In the meantime, if you have a child in your class who is inattentive, hyperactive, impulsive, constantly demanding attention, socially clumsy, overpowering, apathetic andor emotionally volatile, he or she may be ADD. To identify it, you’ll need help, as you will in dealing with day-to-day management. There is training. But you have to know what you’re looking for - and at.

Jenny Lyon can be contacted via the International Psychology Services, 17 High Street, Hurstpierpoint, West Sussex BN6 9TT