probably a school shooting because of some kid whos been bullied way to long
plus kalphiter or ephialtes pushing everyone into lockers and starting fights in the hallway, bubbagum being the hot chick who every guy wants to bang, badspot being the princable who's at the near edge of ending his life perhaps, all the kids below 13 being neclected right off the bat, magick mage fluttering through the hallway giving people prayers, and every furry / brony starting foodfights and being flamboyant friends in the hallway
we'd have no sports, every computer would have blockland, and we wouldn't be able to read.