Offering teenagers cash to do well in their GCSEs is likely to have little impact on their results, according to new research.

While parents may use financial incentives to motivate their children to get good grades, a new study indicates that doing so may well be pointless.

But the prospect of a trip or outing in return for doing well in their school work could encourage pupils struggling with maths to do better in the subject.

More than 10,000 teenagers in 63 schools studying for GCSEs in English, maths and science took part in the research project run by Bristol University and the University of Chicago, which covered two different trials.

In the first, pupils were told that they had £80 at the start of each half-term and would lose £10 if they missed a set target for attendance, the same for behaviour and £30 for classwork and homework.

For the second initiative, students were allocated eight tickets at the beginning of each half-term and promised a trip or outing if they retained 12 tickets by the end of the half-term period.

They lost one ticket each for missing the attendance and behaviour targets and three for missing the classwork and homework goals.

In each of the schemes, the rewards were based on a theory of "loss aversion" - which says that people dislike losing something more than they like gaining something