At the start of the road-safety presentation, a group of young apprentice mechanics laugh and joke. But as Lynda Hudd tells her story, they are visibly shocked.
Her daughter Rebekka was killed at the age of 11 by a driver who was talking on a mobile phone. "She would have been 21 now," she says. "She should have been enjoying her life like you lot."
Since Rebekka's death, Mrs Hudd, a 50-year-old care assistant from Pucklechurch, near Bristol, has become a passionate road-safety campaigner.
She and other bereaved parents are holding workshops in colleges, schools and youth clubs in the run-up to National Road Safety Week, which begins on November 6.
The campaign is organised by Brake, the road-safety charity. This year's theme is young driver and passenger safety. It aims to highlight the fact that road crashes are the biggest killer of 15 to 25-year-olds in the UK.
While only one in eight car driving licence-holders is under 25, more than one in four drivers who die on the roads is in that age group. In 2004, 151 drivers aged 16 to 19 and 291 aged 20 to 29 were killed on British roads.
Mary Williams, chief executive of Brake, said: "This year, we decided it was essential to put the spotlight on young drivers. Too many young people still think racing, drink-driving, talking on mobiles while driving - and even not belting up - is cool and will impress friends.
"But these are the very reasons that so many drivers are dying young on our roads and taking their young passengers and other road-users with them."
Mrs Hudd's workshops with the trainee mechanics, aged 16 to 21, at City of Bristol College's transport technology centre, begin with them filling in a confidential survey. It contains questions about illegal driving, whether they have driven after drinking or taking drugs, and the speeds at which they drive. Then she runs a DVD called Too Young To Die in which parents and friends of crash victims are interviewed, as well as members of the emergency services.
These case studies often feature harrowing scenes and are interspersed with sobering accident statistics. One interviewee is Barbara Pearce, a former teacher who was left disabled after she was trapped in her blazing car. Two men in the car that hit hers head-on both died. The young driver was two-and-a-half times over the drink-driving limit and had been taking cocaine and cannabis. Neither wore a seat belt.
Mrs Hudd shows another film, this time featuring herself talking about her daughter's death. Rebekka was helping her older brother with his paper-round when she was knocked down.
"There were two pools of blood," she says. "One where she had been standing and one 70 feet away where she landed."
When the lights go back on the room is silent. "Most of you will probably realise that was me," she tells them. "That was my daughter, Rebekka.
That's the reason I do the road safety - to protect you. I don't want anyone to go through the agony we have had to suffer."
Finally, she hands out another sheet of paper. This is a pledge to drive safely, stating that they will respect speed limits, not drink or take drugs and drive, and always belt up in the front and back of cars.
As another group of students file in for a workshop, Mrs Hudd makes no apologies for her hard-hitting approach.
"They need to be shown the gory parts - the worst bits," she says. "Because just telling them 'Don't drive fast, don't drink, don't take drugs, don't use a mobile phone while driving' doesn't work. 'It won't happen to me,'
"But if they see the carnage that is involved, it has more impact. We may only save one person from having to go through that. Hopefully, we'll save more."
Gary Jordan, a 19-year-old apprentice, who has been driving for just over a year, says it shocked him. "I don't know whether it will make a big difference to a group of lads, but it made me open my eyes anyway," he said.
Fellow student Aaron Dart, 17, said: "Not many of my friends drive, but people I know from my area in Southmead, they just nick cars and race them round. And you think 'what idiots!'.
"I almost got hit by a racing car a couple of months back. Luckily, I jumped out of the way of it. It didn't stop - didn't even slow down."