Though it doesn’t advertise the fact, “Fist Fight” is essentially a reimagining of 1987’s “Three O’Clock High” with the main characters changed from high school students to a couple of warring teachers. Maybe the makers downplay the pedigree because Phil Joanou’s frantic teen farce was a bomb, little remembered today. But making the combatants older doesn’t mean the new picture is any better—and it certainly doesn’t mean that it’s any more mature. It ends up a typical contemporary R-rated comedy, confusing coarseness for humor and nastiness for smarts.

Though Ice Cube is technically the star, the picture is mostly a vehicle for Charlie Day, a nervous, nebbishy comic of modest stature who has had supporting roles in a number of pictures—most notably the “Horrible Bosses” movies. Under the flabby direction of Richie Keen (who directed him in his TV series “It’s Always Sunny in Philadelphia”), he plays Andy Campbell, a dedicated but milquetoast English teacher at Roosevelt High in Atlanta. It’s the last day of classes before summer break, when students traditionally play incessant pranks, so their treatment of him will be even more insulting than usual. He’s also under instructions from his pregnant wife Maggie (JoAnna Garcia Swisher) to be sure not to miss the afternoon talent show where he’s to do a song-and-dance with their tween daughter Ally (Alexa Nisenson) at her school. As if that weren’t enough pressure, budget cutbacks mean firings, and he has to appear before Principal Tyler (Dean Norris) and Superintendant Johnson (Dennis Haysbert) to make the case for keeping him on.

As bad as things are, they get worse when Roy Strickland (Cube), a mad-as-hell History teacher determined to keep his students in line (and studying) at whatever cost, demands Andy’s help in getting a VCR to work in his class. (The school won’t pay for a DVD player.) When Andy unmasks the culprit—a snarky kid named Neil (Austin Zajur) who’s using his smart phone to interfere with the playback– Strickland goes berserk, smashing up the classroom with an axe, and when Tyler demands to know what happened, Andy fingers Roy, who’s fired and promptly snarls that he expects his turncoat colleague to meet him in the parking lot after school for the kind of beat-down every snitch deserves.

The rest of the movie consists of poor Andy’s futile attempt to avoid getting pulverized while checking off all the other items on his to-do list. He starts off with a sniveling apology, and when that doesn’t work will resort to negotiation and then increasingly underhanded means, including trying to get Strickland arrested. Nothing works, of course, and the last act consists of the fight—a prolonged and, to be honest, unpleasantly bone-crunching business publicized on the Internet, which nonetheless ends happily for both men for two reasons—one entirely predictable, the other ludicrously implausible.

Andy’s odyssey through this day from hell includes a few ancillary characters. Among them are Tracy Morgan as the clueless school coach, Jillian Bell as an oversexed guidance counselor with the hots for a graduating senior, Christina Hendricks as a surly French teacher and Kumail Nanjiani as a “who me?” campus security guard. It’s gratifying to see that Morgan is back on his feet, but his obvious improvisations (including a tacked-on post-credits scene) show no flashes of comic genius, while Bell’s routine as a woman who would gladly bed underage kids is frankly more unsettling than funny, Hendricks is merely shrill and Nanjiani’s major contribution is to slow things down from an otherwise frantic pace. Norris gets a couple of over-the-top shouting scenes, but Haysbert and Swisher are totally wasted in nothing roles. Zajur makes you want to strangle him as much as Strickland does, if that’s a compliment. (The crudity of most of the jokes in which the students are involved, overall, is pretty ugly. Bring in Betsy DeVos!) The talent show sequence with Nisenson is meant to be one of the movie’s high spots, but based as it is on the tired cliché of kids saying naughty words, it represents an opportunity lost.

As for the stars, Ice Cube growls and scowls in his customary fashion—it seems not to bother people much that Strickland is close to being a thoroughgoing psychotic—but it’s Day who’s intended to move to the next level here—the way Cube helped Kevin Hart to do with the “Ride Along” flicks—and it’s unlikely he will. He comes across rather like a modern version of Don Knotts, the mild-mannered, easily frightened little guy who explodes—ineffectually—once in a while. He does the shtick reasonably well, but like Knotts—or Gene Wilder in “The Producers”—that’s an act that works better in a supporting role than at center stage, and it pales here.

“Fist Fight” lands a few—very few—glancing comedic blows along the way, but for the most part it’s a punch-drunk piece of R-rated raunchiness, and a depressing example of the genre.