As the examination season approaches, thousands of students at Britain's new universities face the threat of expulsion for non-payment of tuition fees.

This could mean being barred from lectures and libraries, not having work assessed, and - most seriously - not getting degrees.

How does expelling students help to achieve Tony Blair's target of 50% of young people under 30 experiencing Higher Education by 2010?

This raises an awkward question: how does expelling students help to achieve Tony Blair's target of 50% of young people under 30 experiencing Higher Education by 2010?

Equally, how will it assist the government's aim of increasing the proportion of young people from lower income households entering university?

There are no national figures for the number of students expelled for non-payment of fees each year.

Debt problems

But some individual universities are reported to have excluded as many as 200 - 300 students each last year.

The National Union of Students has called for national records to be kept.

It estimates that up to one in five students drop out each year. While the reasons for dropping-out will vary, the NUS believes debt is the predominant factor.

Maintenance grants

Of course, it is not just the annual fee of �1,050 that has pushed students into debt. More significant was the "freezing" and then, from 1999, the abolition of the maintenance grant which used to cover students' living costs.

The great majority of students now receive only a loan to cover their rent, food and travel costs.

It is when that loan runs out - or when students are too nervous of debt to take out a loan at all - that it becomes difficult for some to afford the fees.

So who is to blame for students being expelled from courses for non-payment of fees? Are the universities being hard-hearted and money-grabbing?

They deny this. For many of them it is a question of survival. It is mostly the newer, poorer, universities which are getting tough with non-payers.

A report from university leaders last summer estimated that �21m in fee payments from students was outstanding. Most universities cannot afford to lose that money.

David Blunkett: Denies any deterrent effect

The Education Secretary, David Blunkett, who introduced tuition fees in 1997, denies there is a deterrent effect on students from poor homes as they do not have to pay the means-tested fees.

Indeed, at present 45% of students don't have to pay. That will rise to 50% from September as the government raises the income threshold below which fees are exempt.

With half not paying, and a further 20% paying only partial fees, just one student in three pays the full fee of �1,050 a year. That sum, of course, only covers about a quarter of the annual cost of the average degree course.

So, with so little paid by so few, was it really worth the bother of introducing fees?

Although there has been no hint of it in public, I wonder if some ministers secretly regret the decision to end the long-standing principle of free higher education just as they were encouraging more young people to enter higher education?

Market forces

The usual market principle when you want to shift more of your stock is to lower, not to raise, the price.

Maybe the government simply assessed demand and decided the market would bear a fee of around �1,000. On one measure they were right: there has been no slump in demand.

The number of students entering university last autumn was the highest ever, up by 5,000 on 1999.

However, while the universities are creating more student places, there are initial signs which could suggest demand is slowing.

Although acceptances were up, the total number of people applying to university last year fell, albeit by only 900.

If expansion is only being achieved by universities accepting a higher percentage of a shrinking number of applicants, this does not bode well for Tony Blair's 50% target.

Mature students: Financial pressures a deterrent?

Moreover applications from mature students, aged 25+, were down by 1% suggesting financial pressures may be a deterrent for older applicants.

It is equally disappointing that university education remains largely the preserve of the better-off, with the proportion of students from the most disadvantaged socio-economic groups remaining static throughout the 1990s.

While 80% of young people from "professional" homes go to university, the equivalent for youngsters from "unskilled" homes is just 14%.

Students whose parents are classified as "unskilled" represent just 1.7% of the university total.

Politically, there is no chance of Labour reversing the decision to charge fees, although they may exempt yet more groups from payment.

Indeed, although the Conservatives would restructure the loans to help poorer students, only the Liberal Democrats are committed to scrapping fees.

'Top-up fees'

However, Labour has ruled out allowing universities to charge "top-up fees" over and above the current fee. This decision shocked university leaders.

The vice-chancellors believe expansion is needed. Politicians want expansion too.

It is no accident that the most advanced economies in the world have the highest percentage of young people in higher education.

So who pays? If it is to be students, then expansion plans could be self-defeating. When Labour came to power they were determined to stay within the former government's spending limits. That was the moment when fees were introduced and grants abolished.

Now, after the Chancellor has released his tight grip on public spending, will ministers think they acted too quickly, and too toughly, on student funding?