When I was in middle school and early high school, I was fascinated by online stories called "creepypastas". They're online short stories that have formed a unique kind of community around them - as if the online space had a campfire at night and users would tell scary tales. I kinda miss their impact on me - I've read way too many for them to affect me the same way xD. But I still get a kick of listening to/reading from time to time, though I'm not 15 anymore. Below I'll list some of my favorite creepypastas of all time.
For my IB Philosophy Final Paper back in 11th grade, I used this story as my stimulus item. This pasta is a story of a man who claims he has nothing to live for and elects to participate in a study where scientists would remove all 5 senses in an attempt for the subject to communicate with god. The extremely unsettling nature of even THINKING about not having senses was enough for me to remember this as a classic. Not very long, I recommend this pasta to many people as the concept is striking and it causes one to think very existentially.
Now, this one is not short. It's very long. However, it won't feel like much time has passed while reading this, given how engaging it is. The story follows a mysterious local access TV station playing odd programming from a man's basement. I won't spoil what they find out, but it's disturbing as f***. This creepypasta is formmatted in a series of dated posts about the poster's findings
I mean, what's more classic than ben drowned. This is arguably a top 5 most famous creepypasta that follows a young man's experience playing a haunted zelda majora's mask game he got at a garage sale. Apparently, the game was owned by a boy name ben prior to the garage sale. The narrator eventually finds out that young ben is dead and has drowned, and he haunts the game and life around the narrator throughout the story. Creepy as hell.