Ricter is likely right. There won't be criminal charges in this one. But the school administration is looney, as is the media reporting.
In North Carolina we thought that law enforcement would not charge the girl in Lee County either. However the law proved to be just as looney as the school officials.
From memory let me outline the Lee County case... a middle school girl was driven to school by her father. Each had a brown bag lunch. By mistake she took her father's lunch bag. The bag had a small non-sharp paring knife for an apple.
At lunch the girl discovered the mistake and immediately turned in the tiny paring knife to a teacher. For this the girl was expelled and legally prosecuted. She was an honor student ranked at the top of her class.