A person can come of age at any time. But in the movies, a lot of that growing up seems packed into the summer months. Especially for boys. That’s when a lad can hang out on the beach, come to some sort of arrangement with girls and endure entirely too much of his closely-observed family for his own good.

“The Way, Way Back” is a semi-nostalgic coming-of-age dramedy from the folks who wrote “The Descendants.” It’s about a shy, put-upon lad, his long-suffering mother, the mom’s difficult new beau and the vacation where a lot of these issues come to a head.

Liam James is 14-year-old Duncan, whose relationship with Trent (Steve Carell), the well-off creep who mother Pam (Toni Collette) is living with, is summed up on the drive to Trent’s beach house. Size yourself up, Trent says, and tell me how you’d rank on a scale of one to 10. The kid shrugs, hems and haws, and says “a six.”

“I think you’re a three.”

Trent is a bully, a guy moving this relationship with Pam and Duncan and Trent’s daughter from a previous marriage into “a family.” A long stay at his house on the Massachusetts shore, where Trent has old friends and “history,” will be the test. A boozy, profane neighbor, Betty (Allison Janney), and the fun couple Joan (Amanda Peet) and Kip (Rob Corddry), ensure that the kids will get an eyeful of adults reliving their more irresponsible past ― the ’80s, with pot, beer and infidelity in the mix.

Lovely Susanna (AnnaSophia Robb) catches Duncan’s eye. But it’s not until he falls into the clutches of slacker smart-aleck Owen (Sam Rockwell) that things look up. Owen lures Duncan into working at Water Wizz, the aged water park that he manages ― whenever he manages to be in the mood to manage it. Duncan learns to ogle bikini babes on the water slides and how to sarcastically win over that special someone ― in Owen’s case, Caitlyn (Maya Rudolph). Over the course of a few weeks, Duncan’s secret job teaches him his true self-worth.

What actors turned Oscar-winning screenwriters (and now directors) Nat Faxon and Jim Rash have done is mash up assorted vacation comedies ― especially “Meatballs” ― into a mother-son vs. mother’s boyfriend melodrama. Rockwell has the amusing goof-off mentor role that Bill Murray played at the beginning of his career, and Collette and Carell et al act out some of the darker corners of “Beaches” and “Little Miss Sunshine.”

Both writer-directors have chewy bit-acting roles as water park employees in the film, which further adds to the scruffy, offhanded feel of “The Way, Way Back.” Trent has restored an ancient station wagon, with its rearmost rear-facing “way, way back” seat giving the film its title. And in this beach town, ’80s music is still the rage. The screenwriters try to avoid writing a period piece about their fondly-remembered past, but don’t quite pull it off.

Like “The Kings of Summer,” the kids often take a back seat to the adult players here, with Carell, in a rare bad-guy role, creating a fully-formed jerk with none of the broad caricature touches that made his career. Collette makes Pam a pitiable figure ― smart enough to see who Trent is, too broken to think she deserves any better. Janney is broad and loud and never funnier than when Betty is telling people how to talk to her son with the lazy eye: “Just stare at the bridge of his nose. That’s what I do.”

And Rockwell, playing another in a long line of larger-than-life eccentrics, turns the frustrated stand-up comic Owen into a slacker icon ― saying “Don’t let the Dahmer glasses fool you” when introducing Duncan to the concession stand clerk (Jim Rash), and dispensing random bits of quirky advice.

“The Way, Way Back” tries too hard to be all things to all audiences ― kids learning about love and life, adults seeing themselves, boozily nostalgic for their youth. But the performances and the ready supply of one-liners make this an amusing look at a new generation getting lost down memory lane.

By Roger Moore

(MCT Information Services)