In the original script, the "F"-word was used 41 times, the "S" word was used 13 times and the "C" word was used 3 times. The uses of these words were later cut down in the final script so as to receive a lower rating of PG-13 (the movie's target audience) as opposed to a rating of R.
The title has several meanings: the "A" refers most obviously to the "Scarlet Letter" of the book and that Olive decides to wear, and "easy" is derogatory, somewhat old-fashioned slang for someone (almost always a woman) who is sexually promiscuous; "easy A" is also an American phrase denoting a school, class, or test that takes no effort to excel at.
When Brandon asks Olive if she will go out with him, she counters that he had just told her that he was "Kinsey six gay." This refers to a system devised by Indiana University sex researcher Dr. Alfred Kinsey in 1948 by which sexuality is placed on a continuum ranging from zero (exclusively heterosexual with no homosexual) all the way up to six (exclusively homosexual). Kinsey hypothesized based on his research that most people fall somewhere in-between zero and six.
Olive's family members are all named after foods: her parents' names are Dill and Rosemary, both herbs; her younger brother's name is Chip, and the one at college is named Kale, and the fact that her name, Olive, is also something edible is the subject of a joke in the movie.
When Anson asks Olive out on a date, he offers to bring over 'The Bell Jar' by Sylvia Plath, and Olive jokes that they could skip the book and just put their heads in the oven. On February 10, 1963, poet and novelist Sylvia Plath killed herself by carbon monoxide poisoning and was found with her head in her oven.
While referring to Micah, Olive opines what he might still be doing in high school at the age of 22. This is an in-joke as Cam Gigandet who plays Micah, was in his mid 20's when Easy A was shot. There were complaints on the Internet, when he was cast, about his being to old to play a high school student.
All the webcam and narration scenes were shot in one day. Emma Stone had a 14-hour day of simply staring at a camera doing every single webcam and narration for the entire movie and every so often she would have to walk around outside to stretch her muscles from sitting so long.
The conversation between Olive and Todd about the penalty for removing his costume head at DisneyWorld was inspired by a lawsuit televised on the CourtTV channel; a family who had been robbed in the Disneyland parking lot sued Disney Parks and Resorts, partly claiming that their children were further traumatized by the sight of character performers with their costume heads off while being escorted to the backstage security office.
The trivia items below may give away important plot points.
Just as Olive's story is a reinterpretation of a novel that is frequently assigned to high school literature classes in the US (Nathaniel Hawthorne's "The Scarlet Letter"), at the end of the movie, it is revealed that Brandon's story is also a reinterpretation of a novel that is frequently assigned to high school literature classes (Mark Twain's "Huckleberry Finn"). Interpreting the relationship between Huck and Jim as a homoerotic one was not the invention of this movie's screenwriter; it has been a fairly common angle from which to approach interpretation of the book since the 1948 publication of Leslie Fiedler's essay "Come Back to the Raft Ag'n, Huck Honey."
In the original script, Woodchuck Todd was Meerkat Todd, and Olive sang a version of the James Bond theme "Nobody Does it Better" (The Spy Who Loved Me) instead of "Knock on Wood" at the pep rally. She also popped out of a dumpster instead of a wheelbarrow of logs.