- Actor-Inspired Element: Emma Watson and Ezra Miller both worked with the choreographer to come up with some ideas for the homecoming dance.
- Actor-Shared Background: Tom Savini, who plays the woodshop teacher, is not only a Vietnam veteran, he's also a native of Pittsburgh.
- California Doubling: Averted. Most of the locations for the movie, right down to the theater where they see Rocky Horror, are filmed in their original locations in Pittsburgh.
- Creator Backlash: Minor example. Emma Watson says she refuses to watch her kissing scenes or the Rocky Horror scene.
- Dawson Casting: Averted with Ezra Miller as Patrick, who was 18, but played straight with 21-year-old Emma Watson as a high school senior. Logan Lerman was eighteen, two years older than his character. Also Lerman is nine months older than Miller, who plays a character nearly four years his senior.
- Enforced Method Acting: The young actors all lived in the same hotel during filming in order to develop believable chemistry.
- Fake American: Emma Watson as Sam.
- Jossed: Stephen Chbosky denies that Candace's abortion subplot was cut to avoid an R-rating. According to him the scene occurred right after Charlie's break-up with Mary Elizabeth - and it was cut so as not to affect the pace of Charlie being ostracised by his friends. The film was rated R anyway and only changed to PG-13 after an appeal.
- Playing Against Type:
- Melanie Lynskey is generally known for playing quirky characters. In The Perks of Being a Wallflower she played the main character's aunt, a child molester who abused the protagonist and later died in a car crash.
- Paul Rudd plays a straighter role than usual, as the Cool Teacher.
- Playing with Character Type: Emma Watson playing a clever, plucky Girl Next Door. But Sam is more of a Manic Pixie Dream Girl than Hermione and has some dark aspects to her past.
- Queer Character, Queer Actor: Ezra Miller is gay like his character Patrick.
- Reality Subtext: Stephen Chbosky is a Pittsburgh native and he watched The Rocky Horror Picture Show in the same theatre they filmed those scenes in.
- Throw It In!: When Sam is reading a card from Charlie, Emma Watson is really reading a personal letter from the director.
- What Could Have Been:
- John Hughes originally had the film rights and planned to make the movie more as a dark comedy. Shia Le Beouf would have played Charlie, Kirsten Dunst as Sam and Patrick Fugit as Patrick. However his sudden death meant that the project was shelved, and eventually made as an independent film with the original author directing.
- A scene with Candace revealing she's pregnant and Charlie helping her get an abortion was cut from the film. It explains why Charlie and Candace's relationship improves afterwards.
- Alice being a lesbian was cut from the original book. Likewise with Sam and Patrick being chain smokers (because in the 90s Everyone Smokes) and Charlie's smoking phase was dropped.
Trivia / The Perks of Being a Wallflower