Surprisingly, the fact that “Kit Kittredge” is based on a doll franchise—the character is one of the “American Girl” series, thus the subtitle—isn’t ruinous: the movie pretty much stands on its own, and no familiarity with its store-shelf source is required. (Actually, there have been a couple of other “American Girl” pictures, but none has been released theatrically until now.) Nor is the reality that it recalls the sort of live-action picture that Disney used to produce five decades ago (and later on its “Wonderful World” series)—though set in the 1930s, it has the sensibility of a movie from the fifties—because at a time when kidflicks have turned raucous and crude, its inoffensive sweetness makes it a positively endearing throwback.

“Kittredge” is rather like a Nancy Drew story that doesn’t clumsily update things to the present, the way the recent movie version of that character did. Abigail Breslin plays the tween heroine in Depression-era Cincinnati, whose beloved father (Chris O’Donnell) goes off to Chicago to look for work after losing his local job, leaving her and her mother (Julia Ormond) to try to keep the house running—which Mrs. Kittredge does by taking in boarders. These include an unhappy mother (Glenne Headly) and her son Stirling (Zach Mills), who becomes Kit’s pal; a beautiful dance instructor (Jane Krakowski); a spacey bookmobile librarian (Joan Cusack); and a travelling magician (Stanley Tucci).

Kit’s an aspiring journalist who hopes to persuade the editor of the local paper (Wallace Shawn) to publish her stories, and when a pair of young hobos (Max Thieriot and Willow Smith) come by the house and become quasi-regulars there, she’s fascinated by their life and takes it up as a subject. It’s an especially topical piece because a midwestern robbery spree is being blamed on hobos, and her friends are accused of some local thefts—including that of her mother’s savings. All ends well, though, as Kit turns detective to disclose the real culprits, exonerate her pals (and the entire hobo community)—and save the family homestead by becoming a paid reporter in the process.

All of which won’t win any prizes for imagination or historical accuracy. But it may teach today’s pampered kids a bit about the Depression, and as family fare it goes down easily, primarily because the young performers are engaging, with Breslin once again demonstrating an ability to connect with viewers both young and old and Mills, Thieriot and Smith complementing her nicely.

Unhappily, as is so often the case in such pictures, the adults fare less well, though Shawn gets some smiles with his characteristic curmudgeonly shtick. Ormond and O’Donnell really don’t have a great deal to do but look alternately supportive and concerned, and though they’re fine, the requirements hardly task their talents. Cusack and Tucci are hobbled by some clumsy slapstick that’s not particularly well staged by director Patricia Rozema. Elsewhere her work is sound but a bit flaccid by contemporary standards, perhaps in deference to the slower pace of life in the thirties. Or maybe she simply wants to give people the opportunity to savor the nice period look fashioned, on an obviously limited budget, by production designer Peter Cosco and costumer Trysha Bakker, and photographed lovingly by cinematographer David Boyd.

Perhaps the expectation that a movie based on a line of dolls is bound to be terrible—remember “Bratz”?—makes “Kit Kittredge” seem better than it actually is. But put-upon parents should be glad not only that the movie isn’t just a big exercise in franchise advertising, but that in more ways than one it represents a return to an era of innocence and social consciousness that seem more and more like endangered species on screen nowadays.