I had just started work at a new school. The first week had been really tiring and filled with the usual chaos of trying to get to know everyone and everything. So when the bell finally tolled 3:15pm on Friday afternoon, I plodded off to my office to take stock and relax for a while. I was sitting at my desk, idly checking emails and finishing off some odds and ends when a rap of knuckles across my office door brought me back from an enjoyable daze. I opened the door and was greeted by fifteen or so grumpy looking teenagers. "Yes?" I enquired of the boy at the front of the queue. He looked at me, puzzled by the question. "What do you want?" I asked him slowly. He looked at me still, "er..." he started in the customary manner for a 15 year old boy beginning a sentence, "it's Friday detention, Sir," he told me matter-of-factly. The next few moments was like getting blood from a stone, but I finally managed to weed out of him that each Friday afternoon, the naughtiest of the naughty, those who had committed some indiscretion so horrendous that their classroom teacher or the Head of Department could not deal with it, were sent en masse to a specially extended two hour detention with the Senior Management. What a wonderful way to end my week, I thought. The students led me to the library where their detention always took place (it would appear that for many of this motley crew this was a weekly routine), and sat themselves at desks looking at me eagerly. "Now what?" I asked them exhaustedly. "You need to give us the questions, Sir," the nominated representative told me. "What questions?" I was beginning to get bored of the whole malarkey. "You need to give us maths questions, Sir. We always do maths questions." My jaw dropped.

Not on my bloody watch. No siree. It transpired that each week, as a punishment, the detention students were made to work through duller than dull mathematics text books. I was absolutely flabbergasted. Bad enough that the students were taking part in the whole pointless exercise of attending a two hour detention every week, bad enough that I had no warning about the onslaught of end of week kids, bad enough that the teachers who had set the detentions in the first place were not able to think of a more creative way of dealing with the problem. But to set mathematics as a punishment: that was taking the biscuit. As a mathematics teachers myself, I know that one of the key missions of the job is to battle against the constant droning of parents, the media, other teachers and society as a whole that mathematics is somehow a preserve of the geeks and the odd. What tosh! So here I found myself in a new school that clearly thought it appropriate to also associate mathematics with punishment. The damage that this would undoubtedly be doing to the subject within the school would have been significant.

Detentions are pointless. They achieve nothing at all. Where they might possibly have some positive impact is when they are used as an opportunity to address the underlying problem. Perhaps the teacher involved will talk to the student about the related incident, or perhaps the student will undertake some task of redemption – litter picking for dropping litter? Maybe the session will simply be a prep hour, with the student catching up on missed homework. I can almost see the point in some of these cases, but overwhelmingly detentions are simply pointless. I state this as a teacher and as a student.

When I was a teenager, each and every Tuesday for years at secondary school, I would have to attend a lunchtime detention. Religiously set by my Religious Studies teacher each and every Thursday afternoon for reasons I failed then and fail now to comprehend. I was no angel at school, far from it, but I was also no bad apple either. For whatever the reason, RS was always chaos and I seemed to have a face that asked for a detention. So there I would sit for 35 minutes during Tuesday lunch, copying out page after page from the Bible. I must admit that having done this for years I do now have a very good knowledge of the scripture and can hold my own in any ecumenical argument, but I am also pretty sure that these weekly detentions played at least some part in the fact that I am nowadays a fully paid up member of the Atheist Club. The sheer fact that the detentions continued week in, week out tells you a lot about their effectiveness. As a teenager, I was fairly reasonable and open to discussion and always thought it would have made infinitely more sense for the teacher to just have a conversation with me about whatever it was that was getting on his wick. Yes, detentions are pointless.

The week following my date with the Friday afternoon detention mob, I announced at staff briefing that the Friday detention would no longer be available as a sanction and asked for an open discussion as to the benefits and pitfalls of the current system and for solutions that would lead to a better system that addressed the underlying causes of poor behaviour.

Teaching can be an exhausting job and there are many people who leave the profession early because they feel demoralised and downtrodden. When surveyed, the teaching profession invariably quotes as the main reason for leaving teaching: the poor behaviour of students. It really is a horrid feeling deep in the pit of your stomach when a class full of students is openly defiant, rude and aggressive. The experience is belittling and humiliating in a way that is unmatched in any other workplace. So it is crucial that teachers find a way to ensure good behaviour in the classroom.

I have been blessed in my career to work with great kids and to have brilliant relationships with them that allowed for a feeling of mutual respect, fun and an understanding that learning is really important. On the whole, I believe that good behaviour is a byproduct of excellent teaching. As one student once said when asked why he had been messing about in a colleague's lesson, "but what if the lesson isn't worth behaving for?"

I often state that kids are kids are kids. No matter where you are, no matter what the economic circumstances, no matter what the culture. Kids are kids are kids. If the lesson is excellent, they will go on the journey with you. Kids are inherently interested in knowing new things.

But, I also know that sometimes all of the spiel, the best teaching, the greatest effort, the most interesting topic, vast amounts of passion and planning and thought can count for nothing at all. Sometimes you will just come across those rare children who are truly broken and hell bent on breaking every opportunity around them. So if detentions and sanctions are pointless, what do you do? When the students simply will not behave, when there is violence, intimidation and a sheer lack of understanding of right and wrong. What do you do?

As a young school manager, I arrived at a new school that I already knew to be in challenging circumstances – indeed that is why I chose the school. My second lesson of the day was with a middle set Year 11 class. The kids arrived and started to sit down. David was a scrawny, ugly boy who smelled unwashed and neglected. He entered the room, asked me "Who the fuck are you?" and then leaped up on to one of the tables. The desks were arranged in a U shape. He marched across the table tops, kicking bags and books of fellow students as he went and all the time staring at me. At the end of the U, he jumped down and walked straight at me until his face was against mine. "So where do I sit?" he demanded.

The lesson got progressively worse from that point in. David was not even the most outrageously behaved. By the end of the hour I felt destroyed. I felt that all of my years in teaching were worth nothing. All of the effort, all of the great lessons, all of the wonderful relationships counted for nil.

Later that evening I sat in my office at school feeling small and alone. I had tears in my eyes as I played out the humiliation time and time again in my head.

So what do you do?

Slowly I calmed down. I said out loud to myself "You either let this beat you, or you sort it." With that, I opened up the class file and, starting at the very beginning of the register I proceeded to call each and every parent of each and every student in the class.

With each phonecall, I would give an accurate, objective and unflinching account of the student's behaviour in the lesson that day. For many of the students this meant that their parents heard of how courteous, polite, friendly and welcoming of their new teacher they had been, how much effort they had tried to put in to learning, and from me a heartfelt apology that I had not been able to give them the type of lesson that they deserved. With this apology came a stern assurance that this would not happen again, an honest conversation outlining the difficulties I had had with some of the students and a description of the action that I would now take to ensure that their child was free to learn in a safe and engaging environment.

For other parents, the discussion was a no-holds-barred threat. Simply put, I told them that it was not the job of the State to raise their children. That the responsibility for their son or daughter's behaviour lay firmly with them. I gave detailed accounts of any disruption caused, any foul language used, any moments of rudeness, any lack of work.

With every parent the conversation ended with a promise that I would call them again following every maths lesson (three times per week). For those students whose behaviour fell below expectations, I would insist that the parent dealt with it urgently. For some, this would mean that I would call them during the lesson on their mobile phone (something I did on three or four occasions to great effect).

I expected, and got, a barrage of foul language and threats from some parents. But with each of these sentences that they spouted, I simply repeated "This is exactly why your child behaves badly. You are the influence. You are taking away their ability to learn. You will stop them being successful. You need to change." You can imagine how this went down!

Wednesday afternoon came round and I was to face the class again. The mood was very different. Most of the students that had been guilty of just getting involved with the spirit of bad behaviour in the last lesson could see that things were not going to be like that and they behaved fairly well. One or two of the students that I had praised, said thank you. But the hardcore of disruptive students were angry. Very angry. The lesson was once again a farce, but nowhere near as bad.

That evening, I sat in my office and made the calls again. Most students were praised. For the hardcore I was completely unrelenting in my insistence that the parent should ensure their child's standard of behaviour met my expectations. For many, the response had now turned to one of not knowing what to do. Parents would tell me how their child was out of control and that there was nothing that they could do to help. I could tell that for some, they really were at wits end. But I insisted further. I told them to enlist the help of their spouse, and other family, I told them to keep encouraging their child to do their best and to remove privileges when they did not. I know that this is incredibly difficult for some, but I was determined that they saw and understood that as a parent they had to play an active not passive role in their child's education. For my part, I deployed every technique and trick that I could muster in the classroom to improve their behaviour.

The phonecalls continued. It was exhausting.

I vividly remember sitting in my office just before the October half term, five weeks since I had first met the group, and preparing to start the phonecalls for that evening with my notebook open wide. There were no students to reprimand. That evening was a delight. Every single student was praised.

These calls were not easy, and the time that it consumed was a very big burden. But, with three conversations per week with each parent, I had built a really strong and, in all cases by October, positive relationship with the parents and students. Come November, Parents' Evening arrived and we met face to face feeling like we already knew each other. So many of the students (all bar two) thanked me for the help I was giving them and for all the praise that they were receiving from me. Many parents told me that their children talked a lot about my lessons and were enjoying them thoroughly.

The class, as it turned out, became one of the most rewarding to teach of my career. I am proud of what I did and happy that the amount of work paid dividends in the long run. There were times in those first few weeks when I thought that I should just throw in the towel. This was especially true when the Headteacher told me that I should not be talking to parents so sternly and that I could not tell them that they were responsible for the behaviour of their child at school. I cannot begin to tell you how sad that made, and makes, me feel. Somewhere along the line something corrosive and horrid has happened to society. There are far too many people who now feel that the State should take care of all of those duties of family and parenting. It is not for the education system to raise children. We play our part, and we play it with dedication and compassion. But if this is not backed with good parenting, then we are at a loss. Are you ashamed when your child misbehaves at school? You jolly well should be. Children reflect their parenting and parents must take responsibility. I know that it is not considered fashionable at the moment to think that people should ever have to feel shame, but I think that this is utter nonsense. There should be a stigma surrounding bad parenting, there should be a stigma about sending your child to school dirty or ill equipped. Society should not treat these things as though they are the fault of some external cause.