How lovely to see this photo again. I haven't seen it for ages. I can tell you that the blond boy, bottom left, is my brother Stephen Tonks who died of cancer in 1991. I can recognise quite a few faces but unfortunately not the names. Two I can tell you are Geoff Trevarthen and Alec Troon who are 2nd and 3rd from the left on the next row down from the back.
Regards
Sue Rigby