I visited a relative in Chicago years ago when I was around 19 or so, being a huge John Hughes fan I had to seek out the "Breakfast Club" school and found out it was actually located in a suburb called Schiller Park , IL , ( "Shermer" was a fictional suburb created various Hugh's movies ) It seemed abandoned or closed but being the adventures type in my youth I tried the doors and was surprised to find one open, I thought if I could just get some pictures of the locations like the library, detention room etc . I entered and walked around inside to looking for the famous library etc, the building was pretty much empty, there were not even typical school lockers against the walls. Instead I finally found a room with several rows of lockers all stacked together when a custodian (guard) caught me and told me the "Library" was just a set built in the Gymnasium then removed after filming, he told me to leave, I had the impression it was not unusual for people to enter uninvited. The school had closed years prior due to lack of attendance and was used only for filming etc. This is me in the image many years ago, sadly I only had a crap 110 film camera
Come to think of it this was also my first trip outside of Canada and would remain the case for many years until I met my wife. As first trip's go that was a pretty good one!