During the decade I've been teaching, the number of children prescribed the amphetamine Ritalin, used to 'treat' ADHD, has simply exploded. It is estimated that 400,000 children are currently prescribed the drug.
In 1991, the number of prescriptions issued was a mere 2,000. When I first started teaching I'd never heard of Ritalin or ADHD.
Now, I can honestly say I don't think there's a single class I teach without at least one and often two or three children being medicated with this very powerful class B drug.
Ritalin has unpleasant side effects - including sleeplessness and nausea - and the penalty for selling it illegally is a maximum of 14 years' imprisonment.
Recent research has linked it to depression, stunted growth, heart problems, insomnia and weight gain and, according to the Medicines and Healthcare Products Regulatory Agency, 11 British children on Ritalin have died.
Serious concerns are finally being voiced about the way Ritalin is being doled out like sweets to thousands of young children
Yet this drug is now routinely prescribed to children as young as six or seven.
Now, finally, serious concerns are being voiced about the way it is being doled out like sweets to thousands of young children.
The National Institute for Clinical Excellence (NICE), which advises what drugs should be made available on the NHS, has just issued guidelines recommending that Ritalin be used only as a last resort.
Parenting classes, they urge, might be more effective in controlling the bad behaviour which has become endemic in our schools and on our streets.
Boys are three times more likely to be diagnosed with ADHD than girls. And looking at the 'symptoms' that characterise it, it's not hard to see why.
Is the child easily distracted and quickly bored? Do they forget things such as instructions, homework and spellings? Do they fidget, doodle and lose things?
If the answer to these questions is yes, then according to the 'experts', the child might well have ADHD. Alternatively, they may simply be a typical boy.
Added to the list of symptoms are, in my experience, extreme rudeness and a dislike of being asked to wear school uniform.
If asked several times to stop talking over me, children with the 'illness' generally swear at me.
When I phone their home, their parents react with the uniform comment: 'He can't help it. He's got ADHD.'
Unsurprisingly, an increasing number of doctors and psychiatrists are expressing the fear that children are being labelled with a mental illness and given drugs for behaviour that in the past would simply have been labelled 'very naughty.'
And anecdotally, there is plenty of evidence to suggest that schools are pressurising parents to put children who cause mayhem on Ritalin.
As a teacher, I'm secretly relieved when I hear that a particularly difficult child, one who won't do any work, who chats and texts through the lesson, who sneers and swears at staff without a second thought, has been prescribed Ritalin.
The drug isn't known as the 'chemical cosh' for nothing. If I'm honest, though, I don't believe that these children are ill. I think they come from insecure, unstable backgrounds where the concept of a bedtime is as fanciful as the fairy tales they've never been read.
I believe that many of the children labelled with ADHD and drugged into acquiescence are simply youngsters who have been raised without any boundaries.
They live in homes where junk food is the norm, where there is no parental control over what they watch on TV and when they watch it, and where authority, whether it be teachers, the police or the lollipop lady, is routinely sneered at and derided.
A study some years ago in America suggested that much of the behaviour labelled ADHD was in fact simply exhaustion, and that children were magically cured of their affliction when they went to bed and slept at night instead of watching gory horror movies.
Personally, I think that many children would benefit from firmer and more consistent parenting.
Of course, having an active, boisterous seven-year-old child is hard work. But it seems to me that far too many mums and dads are happy to have their children labelled with a psychiatric condition and drugged - even if the existence of the disorder is hotly disputed by the experts.
Youngsters might be turned into wide-eyed, slow-witted zombies, but at least they're not running amok in the playground and inconveniencing their parents by getting suspended.
Ritalin, like Valium, has become mother's little helper. It relieves parents of the responsibility of actually having to discipline their children. But as a society, we may pay a very high price indeed for drugging a generation of our children.
Comments? Do you have a child that has been diagnosed with ADHD? Has a school pressured you to medicate your child?