People who grew up in Scotland will probably remember that the idea of a boy wearing school knickers, while not an everyday thing, was not quite as extraordinary as it would have been elsewhere.
This came partly from the kilt and although some people say that the ‘real’ tradition is to wear nothing underneath, in my experience that was absolutely unknown. A boy would no more go bare under the kilt than a girl would go without knickers under her skirt. What one was supposed to wear were ‘trews’ (also known as ‘breeks’ – Ed), which were little woollen shorts, traditionally in dark green.