Music for Young Players was a series of publications intended to be performed by youth with or without prior musical experience. The series is now described in the series of articles in the British Music Collection (links below), by Duncan Chapman (composer, sound artist, musician). The curated set of pieces and articles present a selection of British "new music" from the 1960s and 70s.
As the author of the overview notices, the inherent drawback of the historical series was that it didn't feature even one female composer. The downside of present day presentation is that the very interesting content is hard to navigate through, hence you may find these direct links helpful:
Part 4: Games is obviously the most relevant for our wiki, but interesting material is to be found in other parts too.
Authors in the series include:
David Bedford, Alan Brett, Gavin Bryars, Brian Dennis, Vic Hoyland, John Paynter, Elis Pekhonen, Howard Rees, Hugh Shrapnel, Howard Skempton, Keith Stubbs, Trevor Wishart.
Huddersfield Contemporary Music Festival and Sound and Music featured some of the activities in their project under the same name:
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