Years ago,the school 'swot' was mocked or bullied in quite refined schools, ladybirder. Children will always bully those who don't fit their idea of normal, whatever that is, be it speaking 'posh' or not. A friend suffered on going to boarding school because her Lancashire accent was not 'posh' like the others'. (She rapidly learnt to speak like them, to save herself).
Teachers have complained that those who want to study are actively discouraged because studying is not seen as 'cool'. The answer may be to have streamed into classes where study is seen as normal and desirable, but even then they may be picked on others.