“Memoirs of a Black Girl” is an earnest micro-budget indie melodrama, a “film festival film” of earnest intent if modest means.

If the ambition to punch above its weight were enough, it might pass muster. But unpolished performances, incessant and inane voice-over narration and obvious plot twists pointing at an equally obvious conclusion ensure that it never escapes its featherweight class.

Khai Tyler stars as Aisha, an over-achiever in her corner of Roxbury, Boston, a teen with Harvard dreams.

Her working class Caribbean mom might not be able to make that wish come true. But there’s a big scholarship in play. If Aisha can maintain her perfect grades and ace the SAT, everything might work out for the best.

But there’s a corner of this predominantly Black high school that hates her “Wikipedia” guts. Mean girl Rudi (Juliette Estime) and her posse have it in for our girl. Grades, her supportive teachers, her BFFs Marcus (Nicholas Walker) and Marisa (Carolina Soto) and “Black girl magic” might not be enough to change Aisha’s destiny.

First-time feature writer-director Thato Rantao Mwosa hurls one melodramatic obstacle after another at our heroine. Her brother’s (Juvan Elisma) always in trouble with the law. And there’s that one time she has to go to the bathroom mid-class, and gets bathed in the scent of pot that Rudi and her minions are smoking, threatens to bring her dreams to an end.

When she’s accused, there’s nothing for it but to “rat them out.” As we all know how impossible it is for a school to keep a secret, Aisha finds herself dealing with online and bus-ride harassment and threats.

We may have heard “Snitches get stitches” a thousand times before, but when drug confiscations, expulsions and arrests compound this “snitching,” we can see Aisha is in serious trouble.

Mwosa does her best to put our heroine in peril, but weak performances — especially by the heavies — defeat her. We never truly fear for Aisha’s fate.

Marcus is, of course, gay and his parents don’t know. Of course. The film’s one light moment might be subjecting the kid to his parents’ and church’s attempts to “pray the gay away.” Even that seems pre-ordained, as if every high school movie has to have not just a character like this, but this very character facing the same treatment such characters have faced in films for 30 years.

The high school depicted here never seems real, the bane of many a tiny-budget motion picture. But how much does it cost to loop in students-in-the-hallway noise to make the place feel lived-in? More attention was paid to the hip hop included in the score than the actual soundtrack. Dudley High sounds like the waiting room of a funeral parlor.

Voice-over narration is a crutch a lot of inexperienced filmmakers lean on, and Mwosa doesn’t escape that trap. She’s constantly having Tyler narrate scenes that visually make the points that the narration is merely repeating, or serve up sentiments that sound trite when someone allegedly high school age announces them to the world.

That goes for the rest of the dialogue. You can appreciate “This ‘aim for the stars’ stuff is for rich white girls, not me” for its sentiment, not for its eye-rolling obviousness and unoriginality. Almost every word out of a teacher’s mouth in this is “After School Special” insipid.

The violence is laughably short of anything a stunt crew or much better actors could have faked.

All that said, the picture moves and the story unfolds apace. The characters, “types” or not, are engaging and the players make us care what happens to them, somewhat.

But that label “film festival film” kept popping into mind watching “Memoirs of a Black Girl,” as in “This isn’t bad. It’s exactly the sort of little film we root for at film festivals.” It’s just not good enough to warrant release outside of them.

Rating: unrated, violence, drug abuse, profanity.

Cast: Khai Tyler, Nicholas Walker, Carolina Soto, Juvan Elisma, Juliette Estime

Credits: Scripted and directed by Thato Rantao Mwosa. A 1091 release.

Running time: 1:16