Image caption The pupil premium may be allocated on the basis of numbers of pupils on free school meals

A think tank has urged the government to ensure that schools spend its £2.5bn pupil premium on the most disadvantaged children.

The Institute of Public Policy Research says the policy is expected to increase the budgets of schools in England by £2,410 for each disadvantaged pupil.

But the IPPR is concerned that the funds will not reach the pupils they are intended for.

The government said data would be published on poorer pupils' progress.

It has not given details of how the premium will be allocated, although one suggestion is that it would go to pupils eligible for free school meals.

No guarantee

The IPPR supports the pupil premium but is concerned that the policy includes no mechanism to guarantee funds will provide additional support to the children who need it.

The think tank says the government's reforms to qualifications and school performance tables make it less likely that the pupil premium will get to the children for whom it is intended.

Under the new system, schools will be held accountable for the proportion of their pupils who get the proposed English baccalaureate.

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Under the government's plans, the English baccalaureate will be awarded if a pupil attains GCSE grades of A*-C in maths, English, a science subject, a modern or ancient language and a humanities subject.

The IPPR argues that this change means schools will have an incentive to focus extra resources on children likely to do well in those subjects, rather than on children receiving free school meals.

It points out that the Government estimates that only 15% of all pupils would gain the baccalaureate under current attainment levels.

But only about 2% of children on free school meals gain an A*-C pass in a language, it says, adding that the proportion achieving good passes across all the baccalaureate subjects will be even lower.

Nick Pearce, the director of the IPPR, said the money should be directly allocated to children who received free school meals to provide catch-up tuition or one-to-one teaching to stretch the most able pupils.

"The government is sending a confused message to schools," he said.

"If the government does not revisit this policy, schools will be encouraged to use the pupil premium to boost the results of the most able."

The think tank also calls for a school report card that includes data measuring the progress of children on free school meals.

Public record

A Department for Education spokesman said that schools were best placed to decide how to use the extra funding at their disposal.

But the department intended to include new measures in the performance tables that would capture the achievement of those pupils covered by the pupil premium, the spokesman said.

It would also require schools to publish online how they have used the additional funding, he added.

The spokesman said this would "concentrate schools' minds" on using the money appropriately.

Labour has dubbed the pupil premium "a con", saying it is not bringing additional funding into the overall schools budget.

Education Secretary Michael Gove insisted at the weekend that the funding is "on top of the schools budget that we inherited".

But he has previously admitted that some of the money for the policy will come from within the education budget, and that some schools will end up losing funding under it.

Including the pupil premium, the government says it will increase real terms spending on schools by 0.1% per year for the next four years.

But the Institute for Fiscal Studies has said this still amounts to a 2.25% cut to real terms spending per pupil, even including the pupil premium.