Ask any adult with a clear enough perspective to remember what it was like between the ages of 10 and 13 and they'll tell you middle school was hell. Those years before and after junior high? A veritable cakewalk in comparison to what it's like being a kid on the verge of becoming a teenager, in the midst of puberty yet still immature and insecure enough to be at your most vicious and ruthless. Based on the book series by Jeff Kinney, "Diary of a Wimpy Kid" is no "Welcome to the Dollhouse," but as a PG-rated family film navigating the frequent pitfalls and rare triumphs of a sixth grade nothing, it's got a certain charm and wisdom about it. Warm and fuzzy nostalgia? Not so much.

Greg Heffley (Zachary Gordon) starts off his first year at Westmore Middle School with aspirations of making his mark and becoming the most popular kid in his whole grade. The problem is that, having not received his growth spurt yet, he's just about at the bottom of the totem pole, surrounded by bigger, older-looking classmates who seemingly got the summer memo on how to blend in. As for Greg and best friend Rowley Jefferson (Robert Capron), they aren't among their peers so much as lost in the background. As the school year marches on, Greg's and Rowley's social standing ebbs and flows as adventures are had, mistakes are made, friends are (temporarily) lost, and some valuable lessons are learned.

Directed by Thor Freudenthal (2009's "Hotel for Dogs"), "Diary of a Wimpy Kid" takes a few minutes to simmer down the hectic, ADD-prone mode it's in, but then finds its footing once introductions are out of the way. The plot remains an episodic affair—there isn't one clear-cut story so much as a series of events in the life of protagonist Greg Heffley—while the tone is similar to that of three Disney Channel sitcom episodes strung together. Still, the former seems about accurate to one's day-in-day-out trials and travails, and the latter makes it more accessible to the target age group without turning things heinously over-the-top or cloying. From the daunting experience that is finding a seat in the school lunchroom, to the injustice of being beat by a girl during wrestling club, to the school musical try-outs to the song "Total Eclipse of the Heart" by Bonnie Tyler, to the cheesy educational films shown in class, to the unwanted visits to the front office, to the school dance, to the way peers come in and out of your life with varying degrees of impact, screenwriters Jackie Filgo, Jeff Filgo, Jeff Judah and Gabe Sachs touch upon a wide range of the hallmarks and memories that come with surviving middle school.

Greg's parents (Rachael Harris and Steve Zahn) are peripheral more often than not, but their harried but caring treatment of Greg seems just about right. Less successful is Greg's obnoxious teen brother Rodrick (Devon Bostick), who gets off on terrorizing his younger sibling. Without so much as a glimmer of humanity, Rodrick overstays his welcome as he continues being cruel to Greg for no good reason. Other characters are better handled. Chloe Grace Moretz (2009's "(500) Days of Summer") is consummately cool and unaffected as seventh grader Angie Steadman, who happily clings to her individuality and urges Greg and Rowley to do the same. Newcomer Laine MacNeil has a gift for comedy as stuck-up Patty Ferrell, the kind of brat who assumes everything must go her way. Her rant at Greg when he threatens to bring down the school production of "The Wizard of Oz" (she in the role of Dorothy, naturally, and he as a tree) is a hoot.

"Diary of a Wimpy Kid" doesn't cover any new ground, per se, but director Thor Freudenthal brings an acerbic edge to the film that compliments its more serious handling of the tight-knit friendship between Greg and Rowley. As the hero and narrator of the piece (just don't call his journal by what it really is: a "diary"), Greg is refreshingly flawed and doesn't always make the best choices. As an 11-year-old, he means well, but can also be selfish sometimes, and the steps he takes to finally correcting the wrongs he has done to Rowley are nicely moralistic without wading into sappiness. Indeed, it is the bond between these two that helps the film stand out from the crowd of lesser, more stereotypical middle school-set pictures like 2001's "Max Keeble's Big Move." Zachary Gordon (2007's "Georgia Rule") is spunky and sympathetic as Greg, while Robert Capron (2009's "Bride Wars") is a standout as Rowley, an earnest, stand-up guy who beats to the rhythm of his own drum and doesn't judge his own self-worth based upon how many people like him. A stronger narrative through-line might be nice if "Diary of a Wimpy Kid," like the book it is based on, earns a sequel. The thought of picking back up with these enjoyable characters in a year or two's time is easily welcome.