Although it’s something rarely one wants to credit for, Laura Terruso will have you know she was responsible for the fart that interrupts a key moment in “Good Girls Get High,” yet it should be clarified that it emerged from pressing her hands against her mouth rather than any gastrointestinal impulse.

“I feel pretty young at heart,” Terruso laughs, explaining how she was able to connect with the teenage protagonists of her second feature and going a long way towards reasoning out how she found herself just off-camera personally making sounds of flatulence to break the tension of a tender scene between Danielle (Stefanie Scott) and Jeremy (Boo Boo Stewart). “Either that or I’m wildly immature, I’m not sure.”

Age has been a state of mind in Terruso’s films, ever since she stormed onto the scene with “Hello, My Name is Doris,” the short she wrote at NYU, about a senior citizen wanting to prove her golden years are indeed her finest, that caught the attention of director Michael Showalter and was adapted into a hit feature starring Sally Field. Shortly after, she made her own directorial debut with “Fits and Starts,” which saw Wyatt Cenac and Greta Lee try their hand at “adulting” over the course of a day that requires more discipline than they are capable of as laid-back Brooklyn-based creatives as they make their way to a publishing soirée, and with “Good Girls Get High,” Terruso tackles the tale of two young women in Sam (Abby Quinn) and Danielle who can’t wait to grow up on the eve of their high school graduation, awaiting a future full of promise until Sam accidentally texts a teacher (Danny Pudi) a nude pic, setting off a mad scramble to retrieve it that’s complicated by the fact that both girls are heavily impaired after taking a few drags from a celebratory joint.

Being under the influence enables the girls to actually act their age after their quest to become co-valedictorians threatened to rob them of the usual teenage rites of passage and as Terruso has specialized in characters defying the expectations associated with where they are in life, she herself has shown a shrewd ability to balance the silly and the serious beyond her years, able to tell crude jokes with unexpected sophistication and knowing just when to cut the sentiment of her compassionate aspirational stories with a sharp punchline. With a truly dynamic duo of actresses in “Landline” star Quinn and Scott, the writer/director gets away with murder while her stars try eluding the authorities and with the film now in theaters and available on DirecTV following a premiere at the Los Angeles Film Festival last year, she spoke about eagerly taking on a teen comedy and keeping it relevant after the project spent years in development, as well as her success at finding strong acting duos and having the chance to refine narratives in the editing room.

How did this come about?

After making “Fits and Starts,” I moved to Los Angeles and one of my first meetings was with this company called Alloy Entertainment that mainly specializes in teen-driven movies. They had this project that they had been developing for a really long time and they asked if I would be interested in coming on to rewrite and direct it. When I heard the premise, “Teen stoner comedy for girls,” I was like, ”You had me at hello. I’m in.” And this was really the first time I’ve worked with a studio on a movie.

I remember you actually were tasked with bringing the budget down – originally, a high school was set to be blown up – but it’s still got a lot of big set-pieces. Was it interesting to figure out how to make this work on a smaller scale?

The original screenplay that Alloy had developed was very, very different from the film we ended up making because it was written to be a big budget movie and it was also written 10 years prior, so our world is completely different. The world of an average teenager is completely different and technology really shapes the way we communicate now as a culture, which is something I think about in all my work — how technology shapes our relationships and our interactions. With “[Hello My Name is] Doris,” she finds this Facebook profile and that sets her off on this fascination/fixation/obsession with this guy and similarly with this film, they text her teacher the boob [pics] and that’s what sets off the whole chain of events. Obviously, that wasn’t part of the initial premise because cell phones and sexting weren’t a thing then, but it’s such a thing now for teenagers I felt it was important to play with that stuff.

How did you find Abby and Stefanie to play this dynamic duo?

It was so much fun working with them because they’re truly those characters — they’re really smart and they’re really driven. We cast Abby first and then the job was to find someone who could work at her level because my writing is so playful and there’s lots of little jokes embedded in there, so if you have the wrong person, it just feels like they’re reading writing, whereas if you have a really great actress, they bring the text to life. The minute Abby read, we’re like, “She’s it.” It just came to life. And then we read Stefanie, she was in New York shooting a movie and we read her alone first, and I remember watching her read over Skype — again, technology was such a huge part of the process — and I was tapping my producer Elysa Dutton’s leg, like, “We found her. We found her.”

I knew she was going to pair well with Abby, but we did a chemistry read where she and Abby both got on Skype on a split-screen and it was just like, “Yeah, they’re perfect. They have so much chemistry.” They didn’t know each other at all then, and their first meeting was on the first day of shooting, which was when we shot an eight-page scene of the girls getting high in the bedroom. Eight pages is quite a lot, especially when the actresses are meeting for the first time, but they were such professionals and we made our day. It was great. And by the end of the shoot, Abby and Stefanie became best friends. That was really wonderful to watch them getting closer and after about a week, they’re often in a corner giggling together and you’re like, “What are these girls off and doing?” Just seeing their friendship blossom was so, so sweet. If you look on their Instagram, it’s just like the two of them, and that’s something I’m really proud of because I feel like when I cast actors to play off of one another, I’m really looking for that chemistry. Even on my new film, the best friends are played by Sabrina Carpenter and Liza Koshy and they also have become best friends in life, so I’m like “I’m two for two!” [laughs]

After “Fits and Starts,” because it shares the same “one wild night” structure, did you get a sense of the rhythm for this and how to keep the energy up without it having much of a plot?

I didn’t really think of it in those terms, but it helped having done “Fits and Starts” to know how valuable the other cast members are when you’re doing a film like that, where all the characters they interact with have to be really great character actors who help fuel the story and help propel it forward. In “Fits and Starts,” we had so many amazing actor who had little scenes here and there and similarly with this, we cast some amazing young talent in the film and I’m really proud of the people we got and the performances we got from them.

Was there anything unexpected that happened that’s now in the film that you really like about it?

That’s something that I always look out for and I think of those as the little gems that make the filmmaking feel alive. There’s the scene where Stefanie and Boo Boo [Stewart], [who play] Danielle and Jeremy, are in the car after they’ve just had sex and it’s like this super-awkward scene — it’s after the fart/sex scene I’m so proud of [laughs], and [Jeremy’s] trying to get out of the door and he can’t, and [it’s because Boo Boo] just accidentally locked himself in, so you see him trying and trying to open the door and it takes him a couple of tries before he gets out. We were dying laughing, and it was a total surprise that we thought was the funniest thing, so it ended up in the movie because it’s a great moment and it feels real.

You actually throw in an animated sequence into the film to explain lactose intolerance. Was it fun playing with that kind of tool?

When we were editing [where] we realized that the narrative needed a container, so all of those direct addresses when Sam [played by Abby Quinn] is talking to the Harvard Admissions Committee, that was all something we constructed and figured out in post. Similarly, that lactose intolerance explanation was something we came up with like, “Oh, wouldn’t it be hilarious if this [happened].” So hat’s the beauty of the process is you figure out stuff before you shoot — I had two months before we shot the movie to do a pretty substantial rewrite and then during post, there’s more writing that you’re doing, figuring out how to best tell the story and get the most bang for your buck and get the most comedy out of each sequence.

Was there a particularly crazy day of filming on this?

Man, every day of filming is crazy. But because we shot overnights for the party scenes, when [Sam] does the megabong thing in the backyard and there’s all those kids and everyone’s cheering and we were in this nice little Pasadena neighborhood, it was a lot. It was stressful because we had to commandeer [those extras] around the backyard. But it was really a fun shoot and it felt more like summer camp. You want people to feel free to fail and go a little too big and it’s important to me that no one ever feels they’re being judged. I try to keep it fun and light and on my films, especially because they’re comedies, I don’t want people to feel like they can’t be silly and say something stupid because there’s no such thing as saying something stupid when you’re making a comedy. Because right next to stupid is genius. They go hand-in-hand.

“Good Girls Get High” is now available on DIRECTV and opens on November 8th in Los Angeles at the Laemmle Monica and the Laemmle Town Center, in New York at the Kent Theatre and in Newark at the Cityplex Newark.