My second postdoc experience hadn't been all that happy. I got fed up of working so much on my own in front of a computer screen all day. Besides, there weren't many jobs going for aging postdocs, certainly not permanent posts. So, when my contract came to an end I contemplated a change in career that might get me a permanent job, and that would use my science experience. Since I had done some teaching in my year out, and some tutorial work during my Ph.D., and enjoyed it, it occurred to me that I might enjoy a career in school teaching.

Getting a place on a Postgraduate Certificate in Education (PGCE) course was easy. They didn't bat an eyelid at my research career, asking me only what kind of teaching style I might have. There is a huge shortage of science teachers: I got a £2500 incentive, plus the tuition fees paid for. Most people were quite congratulatory about my public spiritedness, although a few warned that I might have trouble with classroom discipline. I was slightly apprehensive about discipline myself, but I thought that I might learn the ropes by doing the PGCE. I was wrong.

During the first term I was greatly encouraged by the atmosphere of commitment to education and the professionalism of the course tutors. I had no less than four professionals to look after me: my mentor and professional tutor at school and my general tutor and curriculum tutor at the department. There was a great sense of camaraderie with the other PGCE "interns," as we were called. We learned the basics of how to teach our subject areas and had lectures on classroom management and on how to give good explanations, as well as addressing special needs and political issues.

The range of tasks that a teacher is called on to do is quite stunning, but also very fulfilling and rewarding. My respect for teachers grew, and so did my self-respect for what I was attempting to do. Teaching has a bad press, but I found it intellectually challenging. The act of planning a lesson and delivering it requires a good understanding of your subject: You have to prioritise the information and present it in the best way. I found myself thinking a lot as a scientist. Imagine trying to introduce the whole topic of energy for the first time. What is energy? What is the best way of understanding it? How to illustrate it? What experiments to set up? I found it quite a responsibility and very exhilarating.

In the first term we spent 2 days a week in school, right from the first week. We had three or four lessons to plan each week -- doesn't sound like a lot, but you have to script everything out to start with, including details of classroom management. This means deciding in advance where you want the pupils to be, when they stop doing one thing and start doing the next, and what exactly you are going to say to make them do this "transition." I found this all quite difficult: You have to plan everything with military precision, down to exactly what equipment you will need. I used to dive out to get the pritt-sticks and encounter the disapproval of my mentor, who told me that this would lessen my classroom control.

As feared, I was finding classroom control hard. My previous experience in my year out had been in Africa, where the pupils were generally well behaved. Here in England, even in a girls' comprehensive, the task was more difficult. To start with, there was no outright rudeness: only a murmur of talking, the location of which was hard to spot. This murmur would gradually increase until I would say, "Please stop talking," upon which it would decrease slightly and then increase again. This process of continually asking for silence was exhausting and gradually the situation would go out of control as pupils themselves would start to call for silence, compounding the problem. The solution is of course to spot the pupils who are talking and call them by name, but this requires sharp eyes and a good memory for names.

The second term is notorious. Interns are in school all week, doing about three lessons a day. I found the actual work of preparing lessons quite tough but manageable: After writing up a Ph.D., very few things seem really difficult! I liked the way the day was very well structured, and there were interesting things to do in the break time, like basketball and Swedish club. The other teachers were quite busy but friendly. Everyone was very professional and supportive, especially the technicians. The pace was fast but bearable. But in the classroom things were not getting any better.

What makes a teacher good at classroom control? This was my downfall, and it all comes down to will-power. You are standing there with a class full of pupils chattering away. How to get them to shut up? You are painfully aware that a good teacher should never need to raise their voice, and that even if by shouting you get a lull, the noise level soon goes up again. As my curriculum tutor said, you have to just keep working at it. I hated shouting and found that if I followed the advice of the books, and just stood quietly, the noise would go down slightly but then up again as they ignored me. Things came to a head in the second term when I tried to confront the class who simply refused to be silent for long enough to let me speak: I started to threaten them with class detention and things spiralled out of control. The teacher who was observing me commented that the class was governing me and not the other way round. I ended up by carrying through the threat but the relationship was lost.

If I were to do it again, I would (again) pick out the ringleaders by name (learning names is one of the most important things you have to do) and just wait until the class was silent, for as long as it took. But a lot of it is a willingness to make a nuisance of yourself. I tended to defer to the pupils, which is fatal. The collective will of a class of 30 14-year-olds is a lot to withstand. But some people can do it: Several of my friends seemed to thrive on it.

Anyway, I left the course at half-term following a review with my tutors. I spoke with all four of the tutors, who were very friendly and supportive. Their attitude was that it was better for me to assess honestly what my chances were of doing well, and to find out what else I might be good at, than to continue in something that was making me unhappy. Their assessment showed I was spending all my time worrying about classroom management and control when another intern would have started to think about less basic issues. For example, I should have been thinking about how to cater for the needs of the less able pupil; at the time I simply threw simplified worksheets in their direction.

But at some point I had to recognise that this was not for me, and move on. I don't regret the attempt, since I couldn't have found out if I was good at classroom discipline until I tried, and I may still use the skills I have learned. But maybe there are less painful ways of finding out.

The PGCE friends I am still in touch with are coping with the course, under a heavy workload but gaining satisfaction from doing a worthwhile job. I have every respect for them. I think some people are cut out for it: I wasn't, but I don't think that has to do with being an ex-research scientist. There were several Ph.D.s in the course and most of them are still going strong. My problem was mostly the issue of class control, but also the whole aspect of communicating with a large class of teenagers. I never quite lost my self-consciousness, with the result that I didn't focus on what the pupils might be thinking. The aspect of trying to address different abilities I never really touched on. However, I haven't been totally put off teaching in some form or other: Since I stopped the PGCE, I've been doing some tutoring, which I prefer to teaching whole classes, and also some freelance scientific editing. One of these days I'll find a full-time career. ...