My school actualy has archery. The storage room has the bows and the gym office has the arrows. The storage room is easy because I have actualy done this you just take a pencil or something and slide it in the door to unhinge the lock. Then when the bows are in my hand I go to the office. Usually it's unlocked so I can walk right in. When I have all of those I go to the wood shop. There are saws chisels crowbars and nails and all the goods. I take off the dull bow tips and sharpen the ends. (Btw my school isn't very well supervised so I actualy could do this). I grab as many weapons as possible and get my friends. I would also grab some of the school bullies and thugs. When every one is ready we would hide in the library because it has some great hiding spots and an up stairs so we would have a height advantage. Then when my master plan is complete I put on some of my favorite tunes and wait.