Parents should not stop pupils from working if they want to, but should make sure the hours worked are kept to a reasonable level, the Taoiseach, Mr Ahern, has said.
His comments followed the release of a report which shows that more than three-quarters of second-level students are involved in part-time work during school term.
The report, prepared for the Dublin Employment Pact, found that one-sixth of these students were working for more than 20 hours a week. Mr Ahern said the report indicated the money was used "for discretionary and recreational purposes" and it helped to give young people "a sense of personal independence".
The report found that large shops and supermarkets are the most popular workplaces for second-level students, followed by restaurant/fast food outlets and pubs/off-licences.
The report also showed that students from disadvantaged schools are more likely to be working during term time.
One of the most alarming findings was that more than three-quarters of Leaving Certificate students were in some form of part-time work. More than 15 per cent of this group were working over 20 hours each week.
Students did not appear to be concerned about working during their time at second level, the survey reported. For example, almost 40 per cent of those surveyed said that it was unlikely such work would make them tired in school. Almost 90 per cent thought it was unlikely that such work might cause them to drop out of school.
Launching the report - which surveyed more than 1,000 pupils in 16 Dublin schools - yesterday in Dublin, Mr Ahern said the expansion in numbers doing the Leaving Certificate had stopped.
"One element of this has been the attraction of readily available employment," said Mr Ahern. He said it also indicated "only so much" can be achieved through traditional programmes.
One of the recommendations in the report is for more flexibility in the way schools operate, so that pupils who want to work can be accommodated. The report's author, Mr Mark Morgan, of St Patricks College, Drumcondra, Dublin, said that joint education and work options should be considered.