Primary schools are facing a crisis after it was revealed that there will be a shortage of 250,000 places next year.
The National Audit Office warns that the biggest baby boom since the 1950s combined with high levels of immigration and belt-tightening parents turning their backs on private education are to blame for the shortfall.
Amyas Morse, head of the NAO, said: "Despite increases in places and funding over the last two years, the Department for Education faces a real challenge, with 256,000 places still required by 2014-2015. There are indications of real strain on school places."
The number of pupils in state schools is expected to soar by nearly a million to 7.9 million by the end of the decade. Last year alone the primary school population went up by 78,000, the fastest rise in a decade.
At least a fifth of schools were full or overflowing last May and the number of infant classes with more than 31 children has doubled since 2007.
Last September, hundreds of primary children were left waiting for a confirmed place as the term began. And around 23,000 began their education at schools their parents didn't want them to attend.
The rising demand has had a significant impact on the average time a child spends travelling to school.
A Department for Education spokesman said: "We will have spent around £5billion by 2015 on creating new school places, which is more than double the amount spent in the previous parliament.
"We are confident that this will meet the local demand that local authorities face." David Simmonds, of the Local Government Association, said councils faced 'unprecedented pressures'.
"If the Government wants to rapidly increase the number of school places it should release money from the grip of Whitehall mandarins and let councils, who have both the legal duty and the local knowledge to deliver new places.'
More on Parentdish: Our primary concern: the stress of securing a school place