80s-Themed Demonic Attack on School

There was a school in the 1980s in a small town. The school was locally known to be haunted by a deadly paranormal secret that the government tried to cover up but there were survivors - yes, survivors - who were determined to help a new generation of students who began experiencing the same issues and were failed by all other adults to figure out what was going on. I was one of the students, at the start of a new school year in 1988, finishing lunch with other students to went downstairs to the ground floor to get to class. There was something a little different about me, I was aware I was weird even though nobody knew me yet. Suddenly, I heard screams coming from somewhere in the school, followed by an inhuman gargled growling of sorts that sent cold shock of fear throughout my body. Like I just KNEW whatever it was would come up after finishing whatever it was doing. There were a few students and teachers who exchanged confused glances but I knew time was limited and I ran to an empty classroom and tried to jump out of one of the windows that was overlooking an orchard and some shrubs, hoping it would break my fall, but I wasn't too high up. One word was repeating in my head "orthodontia" which I just found out is an irregularity of teeth. Anyway, I jumped. My fall was softened by some plants and I ran to the nearest house to seek help/shelter. The neighbours next to this house that sheltered me offered to help as well - they had answers about what was really going on at the school and offered to help investigate because they were former students who survived.