A group of education organisations is to lobby the government to try to improve school play time.
The group wants minimum standards for playgrounds
The group - three charities and a union - says academies and children's centres are being built and schools rebuilt with little thought to their grounds.
Play is being side-lined and national guidelines are needed to ensure children have good places to play.
They are canvassing opinion from teachers, parents and governors.
The groups involved - Playlink, the Association of Teachers and Lecturers, Learning through Landscapes and ContinYou - have set out their vision of what good play should involve and how it can be encouraged.
Peter Carne, of Learning through Landscapes, said: "We will develop a statement on play that affirms how vital play is for children's learning and healthy development that can be used to support all those who work with children and young people in educational settings".
The group wants want the government to place a statutory duty on local education authorities to provide play-friendly areas in school grounds and to ensure all day care and early learning centres have adequate outdoor space.
It will also recommend introducing national rules or guidelines to set the same conditions for children's play in schools across the UK.
Mr Carne said a lot of investment was going into schools at the moment - but some planners were giving little thought to what went on outside the school or play centre building.
"Millions are being spent on the new academies and on rebuilding schools but some of the grounds are terrible," he said.
"If we don't think about playgrounds in schools, we are missing a great opportunity."
With the government's "extended schools" programme, children would be spending even more time in a school environment and it would become even more important that they had access to good play facilities.
He said there were many examples of schools which provided great play opportunities - but too many which did not.