I used to volunteer as an IT administrator in a local primary school here in Ireland. As I also had a day job, often I would find myself in there late at night because naturally I would need to spend some time with my family, eat something, maybe nap a little before I could take time to go into the school and look at some issues for them. The building is old, built in the 1800's, it was owned by the christian brothers but later transferred to the state in the 90's I believe. To the best of my knowledge, it always was a school.
Having been a volunteer there for 10 years, I have been in and out of the building at strange times, however most of them at night and some stretching until 1am or even 2am if I was running a refresh on all the systems. During that 10 years I certainly got spooked a lot, everything from hearing noises, to actually having to check the playground at 1am because I could hear lots of children playing outside, a sound commonly heard there every day during school hours. I am not someone who is scared or unnerved easily, I personally think I am OK with hearing stuff, but I do think I would flip out if I seen something, which is why I put up with it for so long.
The building itself is a very large building, but the strange activity only happens in a certain section of the building which is the junior area of the school. Most of the classes located there would be for kids aged 5-7.
The strange activity I was most used to be the sounds of kids playing in the playground at night as I mentioned, and also the part of the hallway which connected with this section of the building, always felt like a curtain of ice. To explain this a little better, as I reach the end of the hallway to that part of the building, I nearly always feel like I am walking through a blanket or curtain of ice, I instantly became cold, like I just walked into a walk-in freezer, and the hairs would stand on the back of my neck, but the rest of the section was fine, normal room temperature etc. It had an odd feeling, almost like you were being watched.
The final straw for me and the reason why I had to quit volunteering was this:
Along the long hallway leading down to that area of activity, there are class photos stretching back to the 1800s, and I never really paid any attention to any of them in all the years I was there volunteering. One day about 3 yrs ago I started to hear whispers, which were not uncommon and heard them before, nothing bad, just like someone is next to you saying "hey" or "look over there". Anyway, I heard a voice telling me "look over there" and I felt myself being drawn to a specific photo frame, as I looked at the photo my eyes went straight for a specific person (out of 20+) and the persons face was familiar to me. After looking at the name list under the photo, It was my dad's brother who had passed away maybe 12 months prior. I had never seen that photo before, I wasn't even aware he attended that school as a kid.
What I could never really understand is why or how I was moved to that specific photo frame and my eyes were put right on that part of the photo first time. It was like something was controlling me and that really scared me.
While the person in the photo had been deceased about 12 months prior to the incident, I was hearing stuff and feeling things for 9 years there, which makes me think, there is something more to that building (specifically that section of the building) that allows a force or energy that I simply don't understand.
There have been other incidents there too over the years. One summer there was an electrician doing some work in the same section of the building where all the activity takes place. He was in one morning early to do some work and (while i wasn't there myself to witness it) I was told he left the building as white as a sheet and refused to come back — we later found out that he had seen what was described as red eyes in the attic space.
Both the school caretaker and I have had other unusual experiences, such as doors being open when we know for sure we closed them. Things randomly falling off shelves, doors slamming, computer mouse cursors moving all over the screens and TV's turning on by themselves.
I have shared all of the above with a few people, the school headmaster knows about it and while he was a little surprised, he wasnt entirely shocked, he didn't give me the "you are crazy lecture" I had expected. The caretaker of the school does believe me, especially about the feelings you get in that part of the building at night. The headmaster had asked me to not make it widely known (I had talked about asking a local paranormal group to come in some night just to experience it) because he feared it would attract a reputation with the school and parents.
So that is my own experience, if its ghost worthy or not, I am not sure.