‘The Duff’: Teen comedy doesn’t quite earn a passing grade

Take “The Breakfast Club,” “Pretty in Pink,” “Clueless,” “Mean Girls,” “She’s All That” and “Can’t Buy Me Love,” put them in a mash-up blender and sprinkle in arguably the most social media references in cinema history, and presto!

It’s “The Duff.”

This is a well-intentioned and sometimes quite sharp high school movie that falls just short of the mark due to a few way-off-the-mark scenes and too much heavy-handed preaching.

The eminently likable Mae Whitman (from the TV shows “Arrested Development” and “Parenthood”) is Bianca Piper, a whip-smart, self-effacing, socially awkward senior who favors overalls and flannels to the latest fashion trends, and would rather stay cooped up her room watching Japanese horror movies than attend school functions.

But Bianca isn’t the stereotypical loner outcast. Her two BFFs, Jess (Skyler Samuels) and Casey (Bianca Santos, and what are the odds someone named Bianca would be in a movie where another character is named Bianca?), are gorgeous, popular, sweet girls who proudly walk the hallways with their nerdy pal Bianca, encourage her to find romance and wrangle invites for her to the popular parties.

At 26, Robbie Amell looks more like a young teacher than a high school student, but he gives a natural and winning performance as Wesley, the hunk-jock “man whore,” as Bianca puts it, who lives next door to Bianca. Wesley’s involved in an on-again, off-again romance with Bella Thorne’s Madison, the obligatory beautiful, vapid and nasty mean girl who describes herself as “pre-famous” and has her best friend Caitlyn (Rebecca Weil) record nearly every second of her life for YouTube posterity.

It’s Wesley who drops a bomb on Bianca that sends her spinning. He blithely informs Bianca she’s a DUFF, i.e., “Designated Ugly Fat Friend” — the girl who’s virtually invisible to others unless they want to use her to get to her more attractive friends.

Just like that, Bianca drops Casey and Jess as friends, and this is one of the weak points of “The Duff.” We’ve come to know Bianca as a smart, perceptive, loyal friend — and in a heartbeat, she deletes-blocks-unfollows-mutes her two lifelong besties, without so much as a heart-to-heart with them?

Even though “The Duff” is based on a novel written by a then-teenage girl, and the script by Josh A. Cagan is generally strong, the constant references to social media grow tiresome, and there are some clunky moments, as when a guy in a shopping mall mistakenly believes Bianca is pulling some kind of prank on him and says, “How many hits did it get?”

Well sir, given that you think you’re in the middle of a video prank, that would mean it hasn’t hit the Internet yet, and it would have, um, zero hits.

On a couple of occasions, high schoolers say, “Viral? Viral!” to one another and then forward a video. Pretty sure that’s not how it works, or how kids would talk in such a situation.

A bigger problem is the speechifying that takes place at the obligatory Homecoming Dance climax. “TheDuff” does a good job of exploring of-the-moment issues such as text-crazed youth and the cruel effects of cyber-bullying, but when Bianca finally stands up to Madison, her speech sounds like, well, a speech. A very long speech.

What does work: the easy, comfortable chemistry between Whitman and Amell, who go from frenemies to friends to maybe something more. A dialed-down performance by the usually manic Ken Jeong as Bianca’s journalism teacher. Thorne’s work as the icy Madison, who is peaking in high school and doesn’t yet realize it.

Director Ari Sandel’s style owes a lot to John Hughes, and why not be influenced by the best of the genre? It’s just too bad the script wasn’t Hughes-worthy.

[s3r star=2.5/4]

CBS Films presents a film directed by Ari Sandel and written by Josh A. Cagan, based on the book by Kody Keplinger. Running time: 104 minutes. Rated PG-13 (for crude and sexual material throughout, some language and teen partying). Opening Friday at local theaters.