The rising demand for primary places is forcing many schools to invest in chairs and desks at the expense of playground equipment, a survey suggests.
As the sector struggles to provide the hundreds of thousands of extra places that will be needed to cope with the population boom over the coming years, new research finds that few schools are spending money on outdoor play facilities.
While expenditure on classroom furniture rose by 13 per cent in 2013-14, almost two-fifths (38 per cent) of the schools polled describe their fixed play facilities as inadequate.
Out of almost 400 primaries answering the survey, 57 per cent say they are "well-provided for" in terms of classroom furniture; the same is true for just 14 per cent when it comes to playground equipment.
Headteachers have claimed that they are having to lead fundraising for new play equipment themselves, owing to the lack of capital funding available.
Budget constraints meant school leaders felt they must prioritise classroom equipment, said Caroline Wright, director of the British Educational Suppliers Association, which carried out the poll.
"While schools receive funding per pupil that can be used to fund these classroom essentials, it is often harder for them to allocate the budget needed for a one-off investment like outdoor play equipment against all the other pressures on school budgets," she added. "Yet given the growing problem with childhood obesity, it would be extremely unfortunate if fewer schools were able to provide their pupils with the chance to experience the joys of outdoor play."
The number of primary pupils in England has risen by 319,000 since 2010; by 2023, the overall primary population is predicted to increase by another 379,000. Earlier this year, the Local Government Association said the pressure on places was pushing schools to "breaking point".
Sue Addison, headteacher of Cavendish junior in Chesterfield, Derbyshire, is planning to raise pound;10,000 for facilities such as an assault course, a climbing frame and climbing walls. The school's playground currently has no fixed equipment.
"We want the best for [our pupils]," she said. "Children do need to be active. But obviously you have to make sure the building is safe and in the right order - you have to have chairs and desks to be able to teach them successfully. It is always a difficult balancing act."
Russell Hobby, general secretary of the NAHT headteachers' union, said: "This represents the dilemma of so many heads. They find they are having to trade off one thing against another. It is only going to get harder as more pupils join the system and budgets get tighter."
An investigation by TES last year found that 35 per cent of schools that were expanding would have to build on part of their playground to do so.
Tim Gill, author of No Fear: growing up in a risk averse society and former director of the body now known as Play England, said that ministers needed to invest more in playgrounds if they wanted children to grow up to be "healthy, active, happy people". He added: "Nicky Morgan has devoted all this money to character-building. If she spent a fraction of that on a thoughtful approach to playgrounds, that would be a great way to help pupils develop grit and resilience."
A Department for Education spokesperson said the government had spent "billions of pounds in the school estate to transform the learning environment for tens of thousands of pupils and deliver great new schools".
"This money is not just for buildings but can be spent on outside areas like playgrounds as well," the spokesperson added. "It is right that they have the freedom to decide how that funding is used - not Whitehall bureaucrats - and they are free to spend it on outside spaces if they wish."
`I've had to go cap in hand to donors'
Joffy Conolly, headteacher of Soho Parish Primary School in London, has spent two years raising money for a pound;232,000 playground redevelopment due to take place this summer.
"We are a very small school and there is no money available," he says. "But we think play is essential for children's development.
"We have a bare tarmac patch and about a third of it has a rubberised surface for sports.
"The new playground is going to be an interesting, varied place for children to play, with a mezzanine deck to expand the usable space. It's very exciting.
"But it has meant that I have been fundraising - having to go cap in hand to trusts and local businesses.
"Education is not simply about the three Rs; play is very important. Children today aren't playing outdoors at home. If they go to a school with an uninspiring little playground and play isn't valued there either, that is damaging and I think it's a huge mistake."