Some of Dot (Adrienne Earnhart)'s lines are lifted directly from films of the 90s including "You're vapor." from She's All That (1999) and "As if." from Clueless (1995).
Each letter on the ransom note is taken from a different pop culture property of the 90s.
Originally the story was meant to be set during the 90s but for budgetary reasons this was changed to present day with the 90s influence coming from the main character's obsession with that decade.
Despite the film being about teenagers in high school, the cast was comprised of 20-year-olds (and up) and the location used for the "high school" was actually a university campus.