How old are you (since middle school is different ages in different places)? Are you old enough to drive yourself to school, or do you ride to school on a bus or with your parents or walk? I'm guessing your under 18 though which means your "property" of the school while your there so your stuck in their hands. That being the case if you can carry your own supplies such as water and food I would defiantly try because you can't always rely on others to protect you, search back a couple years for my story about the law firm my wife worked for evacuating the lawyers before the staff as they took care of the important people first. Even if you don't have your own transportation I'd try to keep a couple bottles of water and some food stashed in the back of your locker. If anything happens and your are a minor then the school isn't going to let you just leave to go home yourself so you may look into ways to communicate with your parents so you know when they are coming to get you.