This, via the Sunday Telegraph, is rather sad:
Shepherds dressed in old sheets, Christmas carols and the competition to see who will play Mary and Joseph… nativity plays have been a feature of British primary-school life for generations. But a survey has revealed that headteachers are watering down or ditching the centuries-old Christmas story in favour of secular tales to avoid upsetting pupils of other faiths. Only one in five schools are planning to perform a traditional nativity play this year. They are now outnumbered by schools that say they will be either putting on a non-religious play, such as Scrooge or Snow White, or giving no performance at all.