This is the gold standard of a play - based curriculum: creative, cooperative play, and the only way to get there is through that second 15 minutes. (teachertomsblog.blogspot.ru)
These standards are often related to certain standards of play (e.g. county, national or international) and can be more stringent for higher skill levels. (educationbusinessuk.net)
Umpires maintain standards of play at sporting events. (jobhero.com)