But the students said they only experienced moderate improvement in their grades, the daily reported.

Covering 600 students and parents, the survey confirmed long-held perceptions of a highly competitive city-state which rewards those with top academic results.

The survey showed that eight times out of ten, parents insisted on the extra tuition classes, with two in three parents saying the aim was to help their kids score well in exams.

In 1992, when the national daily carried out a similar survey, concern that children could not cope with the subject was the top reason.

The relentless drive on children to perform academically has led Singaporean Education Minister Teo Chee Hean to plead with parents to tone down the pressure.

"It's not a good thing for a parent to be caning his child just because he failed his exams," the minister said over the weekend.