Colleges will next year be asked to play a much bigger role in the education of school pupils under plans announced by Ivan Lewis, the skills minister.
Mr Lewis revealed a massive expansion in two vocational training programmes provided by colleges and training organisations for 14 to 16 year-olds.
The Young Apprenticeship scheme will recuit 2,000 teenagers, twice as many as it did this year. The Increased Flexibility Programme (IFP) which trains 120,000 pupils in colleges, will also be expanded.
But the Association of Colleges fears that some colleges will be forced to withdraw from the schemes unless they are given extra funds.
John Brennan, the association's chief executive, said: "Ministers have offered only a small funding increase this year. There is disquiet from college principals that, without a decent settlement, many will be unable to continue the programme.
"Some colleges have already held back further recruitment from schools partners because they were unable to subsidise the programme from their own funds, or cut other courses to meet the costs."
The AoC said the Government is providing pound;38 million for the IFP in 2004-05. It estimated the costs of the scheme for 200,000 14 to 16-year-olds would be pound;82m by 2006-07, rising to pound;146m by 2007-08.
Natfhe, the lecturers' union, voiced concerns about training for college staff working with pupils as young as 14.
Barry Lovejoy, head of the union's colleges department, said: "Natfhe has tried to ensure that proper guidance is provided on the new responsibilities this brings to lecturers.
"There must be appropriate time given to the professional development of staff to ensure this.
"All these initiatives for more 14-year-olds in colleges reinforce lecturers' frustration with the differential funding between colleges and schools and between teachers' and lecturers' pay."
Already 1,000 pupils are on Young Apprenticeship programmes in which they spend two days a week out of school, typically one day with an employer and one at a college.
Mr Lewis said that the second intake next September will involve 2,000 14-year-olds. They will work towards nationally-recognised level 2 (GCSE grade A to C equivalent) vocational qualifications.
He also announced more vocational and work-related learning opportunities under the Increased Flexibility scheme for 14 to 16-year-olds, with an extra Pounds 4.25 million to be spent this year on resources and materials to support the scheme.
The programme is now in its third year. Pupils generally study at a college or with a training provider for one or two days a week throughout key stage 4.
Charles Clarke, the Education Secretary, has agreed to fund a fourth intake of students from September 2005. The programme has led to 295 partnerships involving some 2,000 schools.
Colleges will also be expected to liaise with schools in drawing up "personalised learning plans" for the teenagers to ensure the national curriculum is covered.
In announcing the IFP extension, Mr Lewis said the programmes have "created enhanced vocational and work-related learning opportunities for young people at school by enabling them to attend courses with training providers, colleges and other agents."
Of the Young Apprenticeship scheme, he said: "This brings vocational learning into the mainstream and offers talented youngsters a chance to experience learning in the environment which suits them best.
"It offers a unique chance to combine school studies with learning alongside skilled workers."