Home Office minister Lord Falconer called on colleges to make more effort after hearing the case of a man who was released from a young offenders unit only to be told he must wait at least four months to enrol at an FE college.
"We need flexible arrangements to ensure young offenders can get into mainstream programmes immediately and do not have to wait months and months," he said.
He condemned the availability of places in college and elsewhere as a "geographical lottery", with just one in six offenders going into full-time education or employment following their release.
"Any gains made in custody are too often lost," he told the Youth Justice Board conference on the role of learning and skills in reducing young offending this week.
The problem of finding college places for young people once they leave custody was first highlighted by the board in November 2001. This coincided with the creation of 155 youth offending teams (YOTs) in England and Wales to supervise people after release. Working with the Connexions youth advice and guidance service, they must find jobs or training places for 80 per cent of young people under their supervision by March, rising to 90 per cent 12 months later.
But by last December just 30 teams reported hitting the 80 per cent target, said Lord Falconer. "The opportunity to redirect their lives outside the criminal community is being lost."
Earlier Lord Warner, chairman of the Youth Justice Board, admitted many YOTs had some way to go but the fact some had already reached the target showed it was achievable, "when people collectively make the effort".
Pressure on colleges to offer more places to young offenders comes at a time when significant progress was being made by trainers inside the youth justice system, he added.
The time offenders spend in education or personal development is being doubled to 30 hours a week, while a successful literacy and numeracy programme will soon be rolled out to all juvenile institutions.
"If you have young offenders locked up, they ought to be able to do something productive," said Lord Warner.
John Harwood, chief executive of the Learning and Skills Council, said post-16 providers knew more places were needed. The LSC's entry to employment programme for vulnerable and disaffected young people, currently being piloted, will be expanded to cover young offenders next month. More than 500 places would be available in the first year, he said.
LSC figures show that just 17 per cent of young offenders enter education on release and, one month later, only 42 per cent are in training or work.