Megan Park who wrote and directed the film cast Shailene Woodley to play Anna, Vada's therapist. Woodley and Park played high school classmates in the teen drama series La vie secrète d'une ado ordinaire (2008).
Director Megan Park said that the character of Quintin came into the script because she thought it would be interesting to have a character who suffers the most (by losing his brother) and recovers the fastest.
The movie purposefully never establishes where it takes place. This is to show that this could happen in any town in the United States because school shootings are so common.
The trauma caused by the shooting is manifested in none of the characters referring to it as such. They always call it something else, such as "the thing, "what happened," "the incident," or "it."