A school in which kids pay to attend. Contrary to popular or incorrect belief, the kids that go there are not all preps or rich kids that buy their way through life and get everything they want. Not all of them have mansions or are snobby assholes. A good majority of them are friendly, down to earth people. The good thing about the environment they see everyday in school is that it doesn't give them the tendency to yell swears in public and have no consideration for others.
The kids that go there know what its like to not have a lot of money. Sometimes the school facilities are pretty outdated and lousy. Their parents do not have that much money, but they know that the tuition for private school is so worth making their kids into decent people.
Kids that go to these schools speak and type with proper grammar: they sound intelligible. They don't write sentences like this: "i don give a fck what you thnk cuz your such a faggot."
A lot of times they can carry a decent conversation. They have good arguments for ideas and issues, and actually know what important ideas and issues are.
Recently I went to a public event down the street and there were so many idiots and jerks there, that I could have bet a lot of money they hadn't ever gone to a private school.