By announcing how much money education would receive until 2008, Gordon Brown forced the Opposition on to the defensive. He also contradicted the think-tank soothsayers who suggested there would be no extra cash available for education.

But the shine quickly rubbed off the Budget surprise, once colleges did some number-crunching. For while there are guarantees that the Chancellor's favourite projects will be reasonably funded, there were worries that other equally worthy programmes could face the axe.

There was some good news. Brown confirmed his goal of reducing the numbers of working people without Level 2 - GCSE standard - qualifications, and increasing the numbers starting modern apprenticeships. There are also planned reforms of young people's allowances.

But there are worries for colleges, too. The Budget allows for cash increases equivalent to about 3.5 per cent a year in 2006 and 2007 after inflation. This is well below the increases we have seen in recent years. Applying this equally to schools, colleges and universities would give further education an extra £700m a year by 2007-08.

Yet the Association of Colleges calculates that to achieve all the Government's goals, for example to pay for extra numbers of 16- to 18-year-olds staying in education or training, we need to see an uplift closer to £1,900m. We know the public finances are tight. But there are two reasons why we believe colleges should do better than universities and schools.

The first is one of equity. Universities will gain from top-up fees. Schools have gained from previous spending reviews and will continue to gain under this new Budget settlement - but teachers' salaries already outstrip those of lecturers, even for those teaching the same subjects.

The second is economic. Our fast-changing economy needs more investment in learning and skills to prevent skills shortages and job losses. Vocational learning is crucial to maintain a supply of qualified young people and adults in the workforce.

Tony Blair said recently that he wanted every young person to continue in education and training beyond 16. I was reminded of this laudable ambition while discussing the possible consequences of an inadequate settlement with Joanna Tait, the principal of Bishop Auckland College in Durham recently.

Her college runs courses for 200 young people aged 16 and 17 who have left school with few or no GCSEs. They need extra individual tuition, which can be costly. "It takes a great deal of effort to help these young people," she told me. "But already we are facing pressure on our core funding to run larger groups, when these students need much more direct support."

Broxtowe College in Nottingham fears similar cutbacks in their basic skills courses for students who need entry-level qualifications before attempting GCSEs. Broxtowe's principal Nick Lewis told me: "With too little money, only the priorities will get funded, and these vital courses will lose out."

Just as vulnerable are many vocational courses that deliver the qualifications the economy most needs, particularly those at Level 3 - technician level. West London colleges already receive only a third of the money they need to meet new demand, and fear courses such as nursing will have to close unless they get a fair settlement.

The headline figure may have been announced. But there are still important decisions to be made about how the education cake is cut. Fairness and economic efficiency should be the Government's most important criteria.

The writer is chief executive of the Association of Colleges