The one-day seminars, run by ex-prostitutes and other people affected by kerb-crawling aim to take the glamour out of prostitution.
The John Schools - named for the American nickname for kerb-crawlers - have proved amazingly successful in reducing recidivism among kerb- crawlers in the US. By April, the first UK school should be running in Leeds.
At the final preparation yesterday, former prostitute Fiona Broadfoot, 27, rehearsed her story in front of a group of volunteers. "At the age of 15 I was exploited by a pimp into prostitution," she said. "I come from a good family but I was a troublesome adolescent and I ran away from home. Unfortunately, on the first night I had the misfortune to meet a pimp."
She described how she never enjoyed sex with punters and how, when she got home, she used to scrub herself "almost until I was bleeding". Ms Broadfoot, who was a prostitute for 13 years, says talking to real punters will be much harder. "I'm just worried I'll want to jump over the desk and smack them," she said.
She gave up prostitution when her cousin, Maureen Stepan, was killed by a client. She now runs Exit, a self-help group for prostitutes.
When Irene Ivison addresses the audience she pleads with the kerb-crawlers to stop picking up young girls. Her daughter, Fiona, was put on the streets by a violent pimp. She had been working for three weeks when she was killed."I'm going to say to you the reason why my daughter went into prostitution and was murdered was because she met a pimp and because you created a demand for her services. All markets need demand. After you have been here today you are not going to have any excuses. It will give you a chance to really think about what you are doing."
Until five years ago Ms Ivison, a physiotherapist, had no idea about the world of pimps, prostitutes and their clients. She and her three children lived in a middle-class suburb of Sheffield. One day she read a newspaper report: "The body of a young woman, aged between 15 and 22 years, has been found in a multi-storey car park in Doncaster." It was her daughter. Fiona had been bullied at school and was unhappy. At the age of 14 she met the man who would become her pimp. Until after her death her mother had no idea Fiona was selling her body.
Ms Ivison showed the audience a picture of Fiona at 14. "She looks all of 14; she's got braces on her teeth!" she said, still uncomprehending how the men she will be speaking to could want to have sex with such a young girl. "Fiona actually said to the man who killed her `It's a good thing my mother can't see me'. Those aren't the words of an adult making choices. That's a child speaking."
Ms Ivison will tell the men not to kid themselves their money helps prostitutes. "Every penny of Fiona's money went to her pimp," she said.
Attendance at the John School will be offered to kerb- crawlers by the police as an alternative to going to court.
They will pay pounds 80 each for the day-long seminar. The money will fund the project and pay the speakers.
As well as ex-prostitutes and their families, speakers will include health- care workers who will warn the men about the risks of HIV. A representative of a residents' group will talk about the nuisance to family neighbourhoods.
The organisers also hope to recruit a wife whose husband has used prostitutes to talk about her feelings.
Julie Bindle, of Leeds Metropolitan University, is one of the founders of the John School. She said: "The school focuses on the problem of kerb- crawling rather than the women, who will just go on to the streets to earn the money to pay the fines." Workers at a John School in San Francisco reported only three re-offenders out of 850 graduates of the school.
Any man who goes through the UK school and still kerb- crawls will find himself in the courts, as will men who go to child prostitutes.