Finally, someone sat and wrote down the rules to yelling Shotgun! When I was in high school, only one of my friends had a car and we developed our own intricate set of rules of when you can or can't legally yell Shotgun! and expect to get the front seat. The shotgunrules.com site is more in depth than anything we ever came up with though.
Oh god. Banning backpacks won't solve anything. The school is sending the message that they assume the worst of their students. Next thing they will outlaw will be clothes because weapons can be hidden in them, then a daily body cavitiy search before class, just as a precaution.