By Alison Smith
BBC News education reporter
Karl's bullying began in primary school, where he was picked on because of his epilepsy.
Ministers say every school should have a strict anti-bullying policy
"They pushed me around, and hit me. My epilepsy got worse at secondary school and I started to have fits every day.
"My dad used to drop me at school and said I had to go in, but one day I got my bags and walked out."
His school offered him one-to-one teaching, but Karl said appropriate work had not been organised for him.
At 13 years old, he decided not to go back to school - and his parents supported him.
After a visit from a Notschool co-ordinator, Karl, who is now 15 and intends to become a mechanic, began learning maths and English online at home with resources provided by the project.
"I can learn whatever I want, in my own time and in my own way," he said.
"I have a mentor I can contact whenever I like and a specialist maths teacher who marks my work."
Notschool gave him the computer equipment he needed to take NCFE exam board qualifications in maths and English.
"It's been incredible," he said. "I can chat whenever I like and have made new friends.
"At school, I didn't have the choice of not seeing those people I didn't want to see.
"There's nothing I miss about school."
Children who are permanently excluded from school will usually be transferred to a pupil referral unit by the local education authority.
But where a child has been bullied and cannot or will not go to school, a school will usually set up a panel of school representives, parents, and outside experts to decide the best route forward and what educational provision they can provide.
Notschool works mainly with children between the ages of 14 and 16 who are not in education for any reason - not only as a consequence of bullying.
Students receive computers with multimedia packages and broadband to work with at home, and all their work is done online.
And it provides "expert days", when they can come to their local Notschool office to learn face to face with somebody in the field they are studying.
"My friends thought all my Christmases had come at once when I was able to do this," Karl said.
But northwest regional co-ordinator Rick Guy said there was no question of Notschool being an easy way out of school.
"This is not a reward," he said.
"We will only take children for whom this is the only appropriate path. We rarely meet children who do not want to go to school."
Breaking a cycle
Jean Johnson, Notschool's project director, said they were working with some of the country's most disadvantaged children.
She said they included "very talented people for whom the current system does not fit".
"We are a project of last resort. Our pupils have been through the system of pupil referral units and everything else the school system offers, and nothing has worked.
"We take away some of the common restrictions of school, and don't force them to do anything, because that clearly hasn't worked in the past."
She added that 1,500 young people have worked with Notschool, of whom 98% have gained qualifications with the NCFE.
The project is being rolled out across the country with the support of more and more local authorities.
"For many we are trying to break the cycle of lack of education in their families for the future," she said.
"I believe everyone wants to learn something. It is a case of finding what that is."
But for Karl, the important thing is to be gaining the qualifications he needs, and rebuilding his confidence.