I ENTER the building and nobody laughs. I approach a woman behind a desk and tell her why I'm here. Not a titter. She points to a group of people huddled nearby. Some are chain-smoking, some staring in a way one associates with refugee camps and detention centres. 'The other comedians are over there,' she says. The test of a real comedian, critic George Nathan once said, is whether you laugh at him before he opens his mouth. None of us is there yet.

Ten men, 10 women, we've come to the Jackson's Lane Community Centre in North London to learn stand-up comedy at nightschool. Our course costs pounds 27, lasts seven evenings and is open to all irrespective of size, age or talent. Our tutors - John Hegley, Charmian Hughes, Eddie Izzard, Tim Clark and Alan Davies - all make a good living by making others laugh. What do we need to be like them? Impeccable timing? A regional accent? A good accountant? A tall, bald man leads us to another room and starts to explain.

According to our course notes, Tim Clark 'comperes regularly at the Comedy Store'. We sit in a circle and he asks us who we are, what we do and why we're here. 'I'm Joey. I'm a window cleaner. I thought this was car maintenance,' says a large Geordie. We laugh, nervously. Four of us are unemployed, the rest have day jobs which include antiques dealing, accountancy and teaching. 'I'd like to do something before I'm 30 that involves really putting myself on the line,' says computer salesman Graham, 29. 'Things that are hardest to do are always the most rewarding.' Except, perhaps, when you can't do them.

After showing us video clips of stand-ups who are already funny, Tim asks us to perform our own material. A man in a double-breasted suit does a routine about the tax system, then a man with pointed ears talks about madness and suicide. Others touch on snails and acne. A stand-up act, Tim says, is like a street at night: the laughs are the streetlamps and 'if they're not close enough together, you soon lose your way'. The first night mostly consists of powercuts.

Believing anyone can become a good stand-up is as sensible as believing anyone can run a sub-four minute mile. In the weeks that follow, however, we are given three good tips: Hold on to the microphone stand - it stops you from waving your arms; always maintain eye contact with the audience; if your routine's going nowhere, stop, suck in your cheeks and say 'and so I shot him]'. (Well, it works for Eddie Izzard.)

One of stand-up's current biggest draws, Izzard was a Jackson's Lane student in the Eighties. 'It's only when you've done a hundred 20-minute spots you'll begin to know what you're doing,' he tells us. By all accounts, he was terrible when he began. Some comedians do a thousand spots and are still terrible. Does this stop them making a good living? Not necessarily. Being awful isn't nearly as much of a drawback as being female. Women stand-ups still have a much harder time than men.

Comedy as illumination is not something our tutors often dwell on: our concern isn't to get people to laugh at politically correct material, it's to get them to laugh. Some manage this often, some rarely. Martin, for example, who is gangling and shy, calls himself 'the secret love-child of Virginia Bottomley and Julian Clary' and devotes most of his act to talking about Morris Minors. It never even raises a smile.

Though none of the men cracks any mother-in-law or Irish jokes, the material differs according to gender. The women talk a lot about sex, menstruation, emotions and hair, the men prefer shaggy dog stories, puns and punchlines. Peter lives in a deprived area of London: 'We organised a neighbourhood watch recently. See - I'm wearing it tonight.' Esmond knows the secret of staying happily married: 'Go out for a candlelit dinner once a week. My wife goes on a Monday, I go on a Friday.'

Natalie is at the Jane Seymour School of Dramatic Art: 'We don't bother about acting much. We just do each other's hair. Don't think it's easy, mind: Felicity Kendal was thrown out for being too hard and unfeminine.'

In our first lesson, Joey the Geordie does a routine comparing his wife to a broken vacuum cleaner. Miffed not to be signed up on the spot, he never returns. But nearly everyone else stays till the end and, after seven weeks of trial and error, all except Martin show signs of improvement.

In the South-east alone, around 50 clubs now provide regular work for comedians. For those wishing to join the hundreds of acts on the circuit, the way in is through unpaid 'open spots'. Also known as 'open sores', these give newcomers five minutes to prove themselves while the audience drinks, heckles or heads for the toilets.

Downstairs at a pub in North London, three Jackson's Lane graduates are revealing the benefits of a good education. Two months after our course, Julie is worrying what will happen to Mickey Mouse if racial tension reaches Disneyland ('he's black and white'); Jack is explaining why he loves parking ('being wheelclamped is a great way to meet new people') and Peter is offering a new angle on mixing politics and sport ('I say they should keep race out of the Olympics - stick to track and field events instead'). All last five minutes without crying or having beer thrown at them. They are, in other words, on their way. Martin isn't. Told by friends that I am to stand-up what John Major is to erotic dancing, I have decided - for the time being, anyhow - to drop the Morris Minor routine and stick with journalism.

David (Martin) Shannon is available for open spots, cancellations and bar mitzvahs. Anything at all, really. Course details from Jackson's Lane Community Centre: 081-340 5226.

'Comedians' opened at the Lyric, Hammersmith, on Wednesday: 081-741 2311

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