Grade: D-

From the look of the trailer, you might expect “How to Deal” to be a contemporary version of “Sixteen Candles,” and the movie, adapted from a couple of “young adult” novels by Sarah Dessen, does in fact share several elements with John Hughes’s 1984 comedy. It too is about a pretty but unhappy high school girl who feels that her family is too obsessed with other matters to have much time for her. The feeling of familiarity is accentuated by the fact that Mandy Moore, who plays the co-ed, looks a lot like Molly Ringwald; they both have the same habitually pouty expression, broken only occasionally by a chipmunk-like smile. One of the family problems that takes attention away from poor Halley is the same as in “Candles,” too–the imminent marriage of her older sister Ashley (Mary Catherine Garrison), with all its attendant difficulties. There’s even a dotty grandmother (Nina Foch) on hand to provide some geezer humor (in this case, the old broad blurts out whatever she likes as the result of overmedicating herself with marijuana).

But there are more differences than similarities. Halley isn’t pining over a boy who doesn’t know she’s alive; like so many of this year’s women, she’s down on the very idea of love, and resists the advances of studly Macon Forrester (Trent Ford), until his sensitivity and persistence finally win her over in the end. And her parents aren’t just forgetful; they’re divorced, and dealing with their own mid-life insecurities and relationship difficulties (dad, an aging hipster played by Peter Gallagher, is marrying a over-the-hill blonde bombshell, while mom, “West Wing” regular Allison Janey, is just beginning a romance with a likable schlub played by Dylan Baker).

These divergences from the Hughes model point up the major departure of “How to Deal” from “Candles.” While the latter, despite its occasional lurches into sticky sentimentality, was predominantly a light comedy, this picture, in spite of its periodic efforts to elicit laughs, is basically a teen-angst soap opera. In fact, it’s a virtual catalogue of catastrophes, from the death of a nice young fellow from a heart attack on the soccer field and an unmarried girl’s unexpected pregnancy to a car crash and a sudden phone call about granny’s life-threatening accident. The script is so crammed with melodramatic incident that there would be absolutely no room for Anthony Michael Hall’s geeky Farmer Ted here. Yet amidst all the doom and gloom the picture veers periodically into embarrassingly farcical bits, such as one in which Ashley returns home drunk from a bachelorette party and promptly gets into a squabble with her straightlaced beau (Mackenzie Astin), or a stiff dinner party with the caricature in-laws (who must be deplorable characters because they hail from Atlanta and still have a–gasp!–black maid), or dad’s florid publicity-programmed wedding. The constant switches in tone are jarring to say the least, particularly when the sticky romantic interludes keep intruding as well. (The “cute” meetings are especially irksome–the one between Halley and Macon is bad enough, but it’s topped by that between Janey’s harried mom and Baker’s nice-guy delivery-man, so contrived it will make you cringe). It comes as no surprise that the screenplay is based on not one but two of Dessen’s books–or that it runs an unconscionably long 101 minutes. (Parents who expect that it will be wholesome entertainment for adolescents should also be aware that it contains some foul language and awfully “adult” situations. It’s hardly like “A Walk to Remember” in that regard.)

Under the circumstances the cast doesn’t distinguish itself. The amateurish Moore and the smirking Ford barely get by, but at that they (and Alexandra Holden as Halley’s best bud Scarlett, a name which might tell you what befalls her) outshine the adults. Janey lacks restraint–perhaps she’s gotten too accustomed to acting for the small screen–and Gallagher is embarrassingly broad. Foch tries much too hard to play the cantankerous grandma. And the Garrison-Astin combination is far from captivating. All would doubtlessly have fared better under a firmer hand than that provided by Clare Kilner, who allows the picture to meander mercilessly and go lax at important points. And after all the commotion, the blatantly feel-good ending is a terrible cheat.

The upshot is that as far as moviegoers are concerned, “How to Deal” serves up a losing hand of mawkish melodrama, cheap humor and insipid romance.