Poor girl isn't too smart. She made what she thought was a harmless status update and was subsequently expelled from school after her teacher read it. You have probably made similiar status udpates in the past and it's just a matter of time before you too get busted.
The lesson is to be careful what you post on facebook. 500 million people use facebook, but how many of these people have had their lives ruined over what they have shared? The numbers would surprise you. Remember, it's not just you who reads your profile!!!