Children who get thrown out of school have problems - and those who also fail at the pupil referral unit have even bigger ones. And perhaps the biggest burden left by challenging youngsters is on society.
But the voluntary-sector training firm Rathbone, based in Manchester, is developing expertise in how to turn things round for these young people.
The company's Choices programme delivers such core skills as numeracy and ICT, but it also teaches soft skills to hard cases. Self-esteem and social interaction don't come easily, but they are essential at work.
Referrals come from many routes - schools, pupil support centres, the Connexions service or youth offending teams. The programme is mainly funded by local education authorities with supplementary money from the Learning and Skills Council.
Nathan Lofthouse is now back in Year 11 after travelling a rough road since Year 8.
"Before I came here, I couldn't be bothered - I just messed around in class," he says.
He was referred to Rathbone by a pupil support unit near the end of Year 9.
Rathbone began to develop a programme for him. This involved a work placement at the Ministry of Defence, then another at a sound and lighting engineering firm. The plan always included the aim of a slow reintegration into his York school.
In Year 10 Nathan witnessed the discipline of the Army at the MoD and began to re-think his attitude towards school rules.
"I've got new friends at school now and I'm going to put my head down and work hard," says Nathan - and if he does well this year, he will get the chance to work with the engineering company in future.
Choices is full-time, and learners are offered a tailor-made package. They attend core sessions in the centre for two or three days a week and have a work placement for the remainder of the time.
Personal skills are seen as vital to success, so each morning starts with a one-to-one session with a mentor. The Rathbone ethos holds that friends and family are a vital source of support. Parents are informed at every point, and awards days are emphatically open to the learners' families.
Tutor groups are small and each student has short-term targets that are reviewed at least monthly. Tutors use a variety of learning styles.
Extended work placements are well-supervised and great emphasis is placed on behaviour towards other people.
Numeracy is one of the key skills at Rathbone, but it is not numeracy as the students might have known it. Rather, it is more likely to be experienced through cooking or other activities that involve weights and measures. Sports, music, ICT and art are also included as well as drugs and alcohol awareness. Groups and agencies from outside are brought in to deliver training.
Most national curriculum subjects are covered, though they are not delivered in a mainstream fashion. The emphasis is on skills for life and providing experiences for the learners that extend their often narrow worlds. For instance. learners cook meals and do shopping for each other.
Turning up on time, eating meals together, using suitable language, listening to others and dressing appropriately are all important at Rathbone. Many participants have no experience of, say, sitting round a table with others and sharing food and conversation.
But, as Rathbone trainer Nik Sharpas says, going out into the world of work is the most crucial factor in developing these young people's self-esteem.
"The learners get a chance to see what the working world is like and have a chance to meet people who may have had similarly difficult backgrounds, but have come through it and got themselves a job," he says.
Rathbone's own figures show that 85 per cent of learners stay the course, while 75 per cent emerge with enough in the way of skills and confidence to continue at 16, either to training, work or a further education college.
When they leave, they have a transitional support worker to keep an eye on them for as long as this is needed - a few months or a couple of years.
Alex Eadie, a 15-year-old learner at the York centre, has successfully completed a work placement in painting and decorating, and he is now very highly motivated.
"I'm looking forward to going to college next week to do construction, painting and decorating," he says.
It is a career that would have seemed impossible when Alex first arrived at the centre, says manager Debbie Malham.
She adds: "By mixing with people at work, our learners start to think, 'If they can do it, maybe I can, too.'"
Rathbone students can be accredited through the ASDAN youth awards, or with various certificates that will be useful in the workplace, including awards in health and safety, food hygiene and first aid. And if learners are suited to GCSEs, they are provided with tutors in relevant subjects.
Rathbone's trainers are not teachers - they often have a background in youth work. They are called by their first names and the atmosphere is casual. But the price of being treated like a grown-up is an expectation of civil behaviour. If learners overstep the mark, sanctions include being deprived of a cigarette break, or they might be sent home.
Rathbone's Choices programme is available nationwide via its network of centres. These are inspected by the Office for Standards in Education, which has been positive about the scheme. Local education authorities are also positive about the provision.
Jan Richards of North Somerset LEA says: "Choices enables us to work in partnership with a provider who has expertise in running vocational courses for those who have become disaffected with mainstream school."
For the 10,000 key stage 4 pupils who come to Rathbone each year, it is a second chance to be part of society.