From left: Gabriel Basso, Moises Arias and Nick Robinson are “The Kings of Summer.”
From left: Gabriel Basso, Moises Arias and Nick Robinson are “The Kings of Summer.”

When a child threatens to run away from home, he packs his teddy bear and snacks. A teenager longing to leave, though, has the smarts to be a little more prepared.

In “The Kings of Summer,” opening Friday, three high schoolers build a ramshackle house in the woods and flee for a season free of parental supervision.

The irony, of course, is that when three teenage boys are left unsupervised, they often act like idiots.

“They have an idea of what men do,” says Nick Robinson, who plays Joe, the ringleader of the group. “Men provide for themselves, and build houses, and kill food, but I think [these three are] very far from actual men.” (Joe hunts for their sustenance at a Boston Market.)

Two of the three boys are fleeing broken families. Joe’s mother is dead and his relationship with his father (“Parks and Recreation’s” Nick Offerman) is deeply strained; Patrick (Gabriel Basso) struggles with parents who are the Chinooks of helicopter parents. The third member of the trio, Biaggio, is possibly the strangest character ever to appear on film; he’s the spiritual heir to Steve Carell’s character in “Anchorman.”

“He doesn’t have trouble at home,” says Moises Arias, who plays the oddball. “He just wants friends and to hang out.”

He’s also not a nerd struggling to fit in with the popular kids. “He’s incredibly secure in himself, but he doesn’t realize he’s that weird. Biaggio gives no f— …” Arias says, pausing for self-censorship, “… freaks.”

The film eventually emphasizes the need we all have for family, even when they drive you bonkers.

“Families do what they do out of love,” Robinson says. “Joe really sees how much his dad cares for him, how his home is important to him. He really needs family on his side.”