According to the director, he was worried that Miles Teller and Shailene Woodley wouldn't get along after he saw them interact at a lunch he arranged. Teller (who was late to meeting because he had been in Las Vegas with friends the night before) was outgoing and energetic, while Woodley, though amused by Teller, was quiet and for the most part kept to herself unless she was spoken to. After the lunch was over and the director was driving away, he noticed Woodley and Teller talking in the parking lot, but decided to leave them alone - he later found out that the two of them spent two hours talking and getting to know each other in the parking lot. Teller and Woodley are now close friends.
At one point during preproduction, the script began to change. Shailene Woodley was worried that the new rewrites would make the story less honest, and at one point even called Miles Teller to tell him that she was thinking of dropping out. Teller managed to convince her to stay on the movie, and the rewrites never happened.
After The Descendants (2011), Shailene Woodley had not been given any scripts she was passionate about making and had seriously considered dropping out of acting to pursue another career. Thankfully this project came her way and she fell in love with it.
In order to secure actress Jennifer Jason Leigh, whose agents were hesitant about the role due to the small budget, producers told her agents that Julianne Moore also desperately wanted the role and if she didn't say yes within that day, they'd give it to Moore.
"Song for Zula" (by Phosphorescent) is featured during the end-credits of "The Spectacular Now" (2013) (written by the screen-writing-duo of Scott Neustadter and Michael H. Weber). It was also featured later in "The Amazing Spider-Man 2" (2014) (directed by Marc Webb).
The director and the screen-writing-duo worked earlier together in "(500) Days of Summer" (2009).
The trivia items below may give away important plot points.
Originally the scene where Sutter's father asks him to take care of the tab at the bar was supposed to end after Tommy walks away from the table. Sutter looking through his wallet, asking Amy if she has any money, and then the two of them trying to put together enough money to pay was all improvised by Miles Teller and Shailene Woodley. The director thought it was such a sad moment that he kept it in the movie.
Miles Teller and Shailene Woodley disagree on what happened between their two characters after the movie ends. Teller believes that the two went to lunch, but that the two would not reconcile since Aimee appears to have grown stronger and has moved on. Woodley agreed that the two went to lunch, but she believes that because of their age and immaturity, the two characters reconciled romantically, despite the fact that it wouldn't be healthy.
The ending in the movie differs from the ending in the novel. In the movie, there is a more hopeful ending for Sutter, and his relationship with Aimee is left slightly open ended. In the book, Sutter lies to Aimee, telling her that he cannot go to Philadelphia right after graduation like they had planned because he must attend summer school. He convinces her to go without him and promises her that he will go once he finishes school. However, Sutter tells the reader that he will never contact her again and will block her email and phone number. The book ends with Sutter drunkenly walking down the street by himself with a bleeding finger that he cut while opening a beer bottle.
In the bar scene, Kyle Chandler tells Miles Teller about Key West and how awesome it is. This is a curious scene because the TV show Bloodline, in which Kyle Chandler plays the main character, is set almost entirely in Key West, Florida. Also, at the end of season 2, Kyle Chandler's character runs away in a car from Key West, something he supposedly did in the past in the movie, and tells Miles Teller's character about it. This is all the more curious knowing that the film was filmed in 2013 and the TV show didn't begin airing until 2015.