School buildings have keys. I think in America, the custodian has them as well as the principal, with probably another copy floating around some place. It should be easy to have multiple sets of keys, especially since you usually buy a lock, it comes with two keys.
Keys are not as easy to come by here. For some reason, there is always only one key. Each classroom and the office have keys, and only one teacher has the key. This means having to wait for a person to come to open the office, have school close early for the day since the bathroom key it is missing, or having trouble opening classroom doors when a teacher is absent. I have seen kids crawl through broken windows to open doors, or have classes combined to have a gigantic classroom when the owner of a classroom key doesn’t show.
Keys can be suck a hassle. I just don’t understand why they cannot make multiple copies…