Secondary schools should encourage free running and graffiti to improve attainment and behaviour, new research says.
Mirrors for pupils to check their appearance and longer lunchtimes are also suggested, amid concerns that secondary students are deeply unhappy about "dull" outdoor spaces.
The report (bit.lySchoolPlaygrounds) by outdoor education charity Grounds for Learning draws on existing research and its own findings from observations in schools, including three in Scotland: Crieff High in Perth and Kinross, Falkirk's Denny High and Speyside High in Moray.
Research is "clear and unequivocal" that play improves health, behaviour and academic achievement, the document says, yet secondary schools' outdoor spaces are frequently "dull and uninspiring".
"'Playgrounds are often of the bleak tarmac variety," the report states. "They feature large open spaces with wind whistling through, with a few seats scattered around, laid out to look good on an architect's plan or to save some budget at the end of a build. In many [schools], the choice of being outside is rejected and legions sit on stairs indoors, interacting with others via social media."
Some pupils said that going outside was "frowned upon", and one school reported: "Our children don't play."
Many pupils felt they had little influence over outdoor areas, and in one public-private partnership (PPP) school there were suggestions that "the company" called the shots.
In most schools "the car dominates", with pupils having to walk through or around them, whereas outdoor teaching spaces go underused. A number of pupils in one school did not even know that it had a nature garden.
Pupils were concerned that lunchtime was being eroded, leaving them scarcely enough time to eat, let alone go outside. There was even a feeling that pupils were being driven away from school grounds.
"At one school, pupils were very clear about the fact that going down into town was not just about fast food but about being able to walk and talk in a more interesting, private environment than the school grounds," said report author Matt Robinson, the charity's outdoor learning officer.
He had seen some inspiring work, however. Speyside High organised a project with a chainsaw artist, Crieff High pupils could walk out on to a skateboarding park and Kyle Academy in South Ayrshire had set up bicycle trail. One of its pupils said: "Being on the trails and cycling downhill makes me feel free."
Some of the most striking outdoor spaces are outside Scotland. In a Norwegian school, a play area has been built with recycled oil rig parts and a London school has adapted its grounds for parkour, also known as free running.
The report recommends graffiti walls - which give a sense of "teenage ownership" - along with spaces to perform music and mirrors for pupils to check their hair and make-up. Secondary headteachers have warned, however, that financial realities will make many of the proposals impossible to realise.
School Leaders Scotland general secretary Ken Cunningham commended the report, but said its timing was "a bit unfortunate" given pressures around finance, qualifications and the curriculum. Extending lunchtimes, for example, was currently "well-nigh impossible", he said.
Mr Cunningham added: "Most headteachers would be delighted to offer the play opportunities exemplified. Few will have the resources to deliver to that extent."
A spokeswoman for the Scottish government said it had put pound;1 million into a three-year partnership with Grounds for Learning to improve playgrounds and create "more inspiring surroundings". The programme would have worked with 50 schools by the end of 2015 and "significantly enriched the play experiences of around 13,000 children," she added.
Bruce Robertson of education directors' body ADES, who has held various outdoor-learning roles, said: "Although we have concentrated much of our effort on the interior designs of secondary schools, we should perhaps work with Grounds for Learning, Architecture and Design Scotland and the Scottish Futures Trust to look at how the ideas in the report can be introduced."