If you like the idea of taking a bite out of your department's teaching load, as suggested in last month's column, be aware that designing and running your own undergraduate practical classes are nothing like being a demonstrator in one of your boss's classes.

For starters, the buck stops with you if none of the undergraduates can get it to work. After all, your idea for the practical is intended to be, quite literally, foolproof, and you'll have sold it to your boss as such. So, imagine the deep personal embarrassment you'd feel if your class were a flop, especially having experienced firsthand the discreet grumbling among your fellow demonstrators when other people's practicals have not quite turned out according to plan. (Now, don't try to tell me that never happened. ...)

A word of warning. There is always a last-minute hitch immediately before the practical. Seeing a practical class in preparation for the first time (rather than just turning up for the demonstrators' meeting) shocked me. When I was an undergraduate, I really had no idea what went into creating a practical class. I seem to remember thinking, "This must have been done at least a hundred times before." What I didn't realise was that even if it was an old favourite of my lecturer, it probably hadn't been attempted since the previous year. In the intervening time, staff have come and gone, courses have changed, teaching equipment has sat unused and may (or may not) decide to work again, and the course co-coordinator has forgotten where he or she saved the master copy of last year's practical schedule. ...

All of this means that preparation usually starts from scratch each year. In my case, the whole practical was new and, in real terms, I was it--as far as personal knowledge and experience went. In other words, the message was: "No pressure Phil, but you're the expert!"

In addition to these revelations, I discovered that running practicals is rarely at the top of agendas for project leaders. A subset of results-hungry research leaders even view all undergraduate teaching as a nuisance. This can lead to a very last-minute approach--an ideal breeding ground for last-minute hitches--you know, those minor inconveniences such as the main assay not working at all. On the day before other people's practicals, I heard the air filled with cries of: "Hold on, check it again, it's got to work!" and "Has anybody filled in a health and safety form yet?" Knowing what I do now, I am amazed that some of the practicals I've had the pleasure of demonstrating in were pulled off at all.

With this in mind, you can imagine my sensibilities on the morning of the big day. I was a little timid, to say the least, at the prospect of introducing and running my own piece of undergraduate teaching. To make matters worse, the class was scheduled for the afternoon, leaving too little time for me to get my teeth into my research but plenty to brood on the potential shortcomings of what I had planned. Even though I'd tested it six or seven times, I still found myself doubting the basic premise of the practical. Was I just being silly? I quickly did the experiment again (its simplicity, otherwise an asset, made it infuriatingly easy to repeat) ... and what relief, what joy, it worked! Again!

And then, before I knew it, there I was, fighting my way through the crowds of students waiting in the corridor. My first impulse was to head in the opposite direction but, against my better judgement, I pressed on and entered the teaching lab. Seeing everything neatly laid out, just as I had requested, calmed me down a bit. At that moment, I knew I was well prepared.

Taking control of and addressing 100 students is not for the faint hearted. To get their attention I, rather surprisingly, found myself bellowing at them as if I were some sort of ex-military type running an Outward Bound course: "OK, let's get started then." I didn't really have a plan for taking control, but it seemed to work. They all turned to listen to me. An unnerving moment followed when I just looked at them and they just looked at me. Weird!

But, before I knew it, I'd dived straight in and started to explain the gist of what they would be doing, referring everything back to my carefully prepared practical schedule. Then came my first true sense of relief. Once I had told them to get started, they turned away and a satisfying hubbub began, with much shuffling and chattering. It was up and running!

In my experience, most students are quite able to read and digest a practical schedule and follow suitably clear instructions. This is, of course, contrary to the sometimes deeply ingrained opinion held by some seasoned academics that most undergraduates are a bit dim. To be modern in our thinking, we should, of course, consider such opinions to be entirely antediluvian and the direct consequence of inadequate teaching skills--not a reflection of the students' alleged ineptitude.

Without a moment's hesitation, I sauntered into the throng. Anyone who showed the slightest interest in asking a question was treated to an enthusiastic dose of encouragement. By this time, I was really eager to see if my experiment would work in their hands. All fear and nervousness had evaporated. I was enjoying myself. Suffice it to say, the practical went well. Although there were one or two groups whose peculiarly ham-fisted approach prevented any possibility of success, most people got it to work and, I hope, learned something.

I also relearned a useful lesson that I once picked up when I was teaching my A-level students: Be prepared to adapt your lesson to the circumstances and, if necessary, cut things out if they aren't working. Trying to be scientific, I had asked the students to weigh out a reagent, although I knew it would work if they just guessed the amount. Seeing the queue for the digital balance, I stood up and filled the air with the cry, "Listen up, just add about half of the 'X' you've got in the test tube." At the end of the day, you want things to run smoothly and students to get the message, not to stick blindly to the schedule.

And on reflection, I reckon I could get into this teaching thing. ...