All the stuff is covered above that you will need.....lets talk about the fun things you can do !
My dorm was shaped like a rectangle. Rooms along the edge and bathrooms/recroom/stairs etc. in the middle of the floor. The doors to the rooms were the perfect distance from the wall across so that you could place your back on the wall and push the bottom of the doors inward about an inch. Why would you want to do that you may be asking? Well....if there is someone in that room and you want to keep them in there for awhile, all you had to do was have someone slide a stack of pennies up the doorjam while you are pushing the door in and then release. PRESTO, they are locked solid in that room until someone removes the pennies
Very effective !!