I attended a boarding school for a couple of years, but I wasn't a boarder. I found the bullying to be slightly different there to other schools that I went to.
In most places, the bullying was outright - violent, lots of insults and teasing, being tripped up, being called names and laughed at.
In the boarding school I went to, it was more 'tame'. They were definitely a higher class of children, which is weird to think about. They were more based on exclusion and ignoring than violence and cruelty. At the time, I didn't fully appreciate the difference but I recognise it now.