Classroom backgrounds needed ASAP

Im making a story were its a prison school? If that makes sense :confused: But i cant find any classroms thats fit the dark/gloomy theme of all the rest of the backgrounds. Does anyone have any? Or know where i can find some xoxox

You might find something you like on there’s a lot of stuff on there

I could find only this one:


Here are a few sites that have free to use images:

Might be worth checking them out x