Struggling pupils' automatic right to one-to-one tuition has been axed in the government's shake-up of England's school funding.
Pupils who had fallen behind in reading or numeracy were to have a right to catch-up help under a number of schemes being rolled out nationally from 2011.
The funding for these successful programmes is now being channelled into the national schools budget.
Head teachers will then decide whether to continue or sign up for the schemes.
Labour had pledged that pupils who fell behind at primary school and early in secondary school would receive one-to-one or small-group catch-up help from 2011.
But tens of thousands of pupils already receive that help with many more due to obtain it under schemes being rolled out across England.
Explaining the decision to head teachers after the Spending Review, Education Secretary Michael Gove said the "ringfences were being removed" from a number of programmes and school grants.
These include one-to-one tuition for secondary children, Every Child a Reader, Every Child Counts for primary age pupils, and a number of other budgets allocated to schools.
Mr Gove said the move would give head teachers "complete freedom over how this money is spent".
This implies the schools currently in receipt of these extra funds will retain them when next year's allocations are made.
But in fact the cash will go into a national budget to be re-allocated to local authorities at the beginning of December.
Schools, however, are unlikely to find out the size of their budgets until after Christmas.
In the meantime, the Every Child a Chance Trust - which runs the Every Child a Reader and Every Child Counts schemes for 60,000 primary school pupils - has been asked to delay the publication of research which could persuade head teachers of the effectiveness of their programme.
This study builds on research which shows that after 40 hours of individual reading help children advance almost two years in their reading age.
On the numeracy programme, gains of more than a year or 14 months are made after 20 hours of one-to-one coaching.
The coalition government had protected the schemes, known as Every Child a Reader and Every Child Counts, until the end of the current financial year.
But schools minister Nick Gibb has told concerned MPs the effectiveness of the Every Child programmes is currently being reviewed.
A Department for Education spokeswoman said: "We believe schools are best placed to buy in support for children who need help with literacy and numeracy in primary schools - it is not for central government to dictate how they do this.
"The department will set out further details on raising standards in schools in a white paper later this year."
General secretary of the NASUWT Chris Keates said the government was using the funds from schemes such as these to make it appear that the overall national schools budget was increasing.
She said these funds would instead be spread across a larger number of schools more thinly.
She added that those in deprived areas would be the ones to lose out, as they had previously received a greater share of these funds.
"No job, no programme and no school is safe under these cuts," she warned.
She claimed Labour had been planning to spend £40.6bn in 2010-2011 - some £1.6bn more than the £39bn promised by the end of the spending review period.
Shadow education secretary Andy Burnham said Labour's commitment to one-to-one tuition for students struggling in the "three Rs" meant that no child would be left behind.
"We support moves to give head teachers greater freedom but removing guarantees for parents at a time when most schools will see their budgets cut means exposing our children to a lottery - some will get this help, some won't."
"For those families currently seeing the benefits of the Every Child schemes, it will be a bitter blow if they lose this support."
General secretary of the Association of School and College Leaders Brian Lightman said there had been a fundamental change in culture, with head teachers being given more autonomy to decide what was best for their pupils.
But he added that despite the promise of a 0.1% increase in the national schools budget, with rising school rolls and inflationary pressures most schools would effectively have less money.