The Labour Force Survey suggests that nearly 50 per cent of 16 to 19-year-olds are undertaking substantial part-time work. Furthermore, anecdotal evidence suggests that many "full-time" A-level students are working between 10 and 40 hours per week.
Our concern is not that young people work while studying, but rather the amount of work many of them undertake and the possible effect that this, combined with other factors, is having on commitment to their studies. Furthermore, this trend is taking place in the context of an overall plateauing of A-level grades and a deterioration in Advanced GNVQ completion rates.
Disturbing evidence is beginning to emerge that it is the weaker students who are being disproportionately disadvantaged by a lot of part-time work. Stronger students continue to gain higher grades at A-level, but weaker ones may be losing ground.
They may study for only 10 to 15 hours a week and, therefore, see their education as part-time, to be fitted in around the demands of their paid work and social lives.
Opinion on the ground, however, suggests that most students are working long hours to support lifestyles rather than out of financial necessity. They may also be from families with little history of full-time participation in post-16 study and who may also expect them to contribute to the family budget.
This situation can be contrasted to the position of stronger students, with parental support, who are working hard for high grades to get into university and who are more likely to "manage" a relationship between a commitment to study and limited amounts of work.
Students are not the only players in what we term the "low achievement conspiracy". Employers and employment agencies appear to be putting pressure on 16 to 19-year-old students to commit themselves to long hours and varied shift work. Many appear happy to have an apparently flexible workforce who can be paid low wages.
While part-time work has always existed, the scale of this phenomenon appears to have increased markedly in recent years as the service sector has grown and as consumer pressure on young people has intensified. This trend may be exacerbated by the move to 24-hour shopping in large supermarkets. Sainsbury's, now for example, employs 290 full-time 16 to 19-year-olds, but more than 12,000 part-timers.
At this point other factors join in leading to a "bare minimum" approach to study. Schools and colleges are reluctant to make demands of students when their competitors are not prepared to do the same. Our qualifications system reinforces this situation because it makes no specific demands for A-level study. Students are allowed to take a small number of qualifications with no national specification on the amount of study required.
Many may well end up taking programmes which consist of just two A-levels or an advanced level GNVQ, both of which at best constitute a bare minimum advanced level curriculum.
In colleges, the Further Education Funding Council funding methodology further compounds this situation by forcing a radical reduction of taught hours for advanced level programmes. Some higher education institutions, worried about the need to expand recruitment, eventually play their part, by demanding very low grades for access to degree courses.
The whole marketised system, therefore, becomes implicated - a vicious circle of actors and factors depressing expectations and, possibly, levels of achievement.
There is little incentive for many 16 to 19-year-olds to follow fuller advanced level programmes or to strive for high grades. It appears that those most affected are the students who need the most support to gain Level 3 qualifications.
So what should be the response? It is tempting to go with the grain by matching qualifications and the learning experience to these labour market changes and encouraging dropping in and out of study. However, we caution against giving in to a casualised labour market because it would involve going in the opposite direction to our international competitors.
Our A-level students receive about half the resources and support of learners in northern European systems who study a broader and more demanding curriculum and have far higher achievement rates at advanced level - a key indicator of a highly-skilled workforce.
Given this picture, what should we do?
First, it is important to recognise that the "low achievement conspiracy" is becoming a serious issue which needs more research. Second, the Government needs to decide whether it wants to see some convergence with advanced level systems in other countries.
One way of doing this might be through an advanced diploma aimed at raising achievement for the whole advanced-level group. Third, we should recognise that part-time work for 16 to 19-year-olds is not a bad thing in itself but that it needs to be managed positively. This could mean establishing collaborative agreements between schools, colleges and leading companies to achieve a proper relationship between learning and working.
Dr Ann Hodgson and Dr Ken Spours work at the Institute of Education, University of London