If you are just beginning to explore boarding schools, this article will give the view from 10,000'. I suggest that you scan the article quickly, and then drill down in anything which interests you. Our site has a wealth of information to guide your search process. And, if you don't find the answers you want, you probably will be able to find them on our sister site, Private School Review. Finally, if you have more questions, tweet me. I will be happy to help.
Size
Boarding schools range in size from rather small (100 students) to rather large (1200 students). Most boarding school populations are somewhere in the middle with 300-400 students. Compare these numbers to most public schools and you will begin to see why size is so important in my opinion. I wanted my daughters to be visible when they went to boarding school. When the school community is a manageable size, teachers and administrative staff get to know their students quickly. More importantly, they will usually know what their young charges are up to. Boarding schools take their role as your substitute very seriously. The legal term is in loco parentis. Your child will not be invisible or able to hide when she attends boarding school.
Chatham Hall is an example of a small school. Everybody knows everybody in a school like this one.