Jack Johnson really missed his calling. Sure, he’s an amazing Hawaiian crooner. Sure, he’s an amazing pro surfer. Sure, he’s an amazing documentary filmmaker. But his feel-good vibe could have made him the coolest gosh-darn kindergarten teacher of all time.

On his newest album, “Sing-Alongs and Lullabies for the Film Curious George.” Johnson has put together 14 honest and humble songs that immediately bring back nostalgia for juice boxes and naptime — everything that is simple and sincere. Underscored by the heartbreakingly adorable liner notes, the album focuses on old-time monkey morals such as recycling, sharing and, most of all, caring. However static Johnson’s usual fare is said to be, here he’s at his best — his infectious optimism is music straight from the heart of this wayward simian.

But this is in no way intended to trivialize Johnson’s achievement. Coming from a background of poetic songwriting, Johnson (or, as I like to call him, “Raffi 2.0”), creates this playful mood without sacrificing any of his emotional maturity.

In fact, from beginning to end, there is an obvious transition of artistic direction. Songs like “Upside Down” and “Wrong Turn” could have easily come from last year’s “In Between Dreams,” while later songs like “3 R’s” show Johnson adapting to the playground world of Curious George.

“Upside Down” is the obvious single that bounces along with a steady bass line and a solid wood-block rhythm. Definitely a contender for a frolicking monkey montage, the song feels perfectly appropriate as theme music for the most curious monkey of all time. Lyrics like “I want to turn the whole thing upside down/ I’ll find the things they say just can’t be found” groove along with the guitar jam as freely as Curious George flies from vine to vine.

The album isn’t all fun and (monkey) games, though. “Wrong Turn,” for example, is a particularly pensive and insightful track that breaks up the carefree romp, introducing more mature undertones to the album. It’s hard at times, to decide whether the song reflects a grown man considering a serious relationship, or Curious George considering a cooky adventure. “And I’ll wait here for now/ Just long enough to be sure/ That you really want to go through with this” — these lyrics could go either way. According to Johnson’s most profound philosophy, perhaps we’re all just a bit curious at heart.

Before he gets too bogged down in pesky adult problems, Johnson and Friends (the amorphous term for amigos like G. Love and Matt Costa) pick it back up with the kid-friendly “3 R’s.” Don’t worry, this isn’t a song about reading, writing or arithmetic — shun those ideas, its about recycling! Maybe it’s the jazzy percussive piano, or maybe it’s the cute kid backup chorus, but the song makes recycling sound like the best way to spend a Friday night.

Johnson’s natural rapport with his much younger collaborators on “3 R’s” is wholly representative of the album’s friendly approach. Except for Ben Harper’s disappointing contribution on “My Own Two Hands,” the entire album is always homey and never preachy or condescending. But Harper’s wilting vocals sound like they would be more at home in Mister Rogers’ neighborhood. Still, even here, Johnson’s easy ukulele picking brings the song back to jungle-gym level.

This natural warmth, which remains definitive throughout the album as well as his previous work, makes Johnson the perfect match for a sing-along album. With the exception of preschoolers and pesky a cappella roommates, haters might feel uncomfortable with the prospect of a sing-along. But even they’ll join in on Johnson’s welcoming and unassuming vocals — his loose guitar licks work like an acoustic version of that helpful karaoke bouncy-ball cue.

It’s this catchiness that makes the album so fitting for George’s theatrical debut. The laid-back album is hardly your usual orchestral soundtrack, but everybody knows that monkeys hate Hans Zimmer anyway. Instead, the movie will be an interactive experience as Jack Johnson and Friends invite audiences to join in the fun. Sing a-long or not, though, the album will always be able to stand on its own — as 100 percent good-natured fun, no preservatives added.