The theme of Lee A. Tonouchi’s new comedy, “UchinaAloha,” is things composite, beginning with its title and extending to culture, language, music, instruments and food.

Uchina stands for Uchinaaguchi, an indigenous Okinawan language, and the play, itself a blend of musical comedy and family drama, centers on the conflict between a local slacker, David (Kenny Kusaka), and his grandfather Tamashiro Sensei (Shah J. Hoshida Bento), an Okinawan immigrant.

The gray-bearded Sensei teaches traditional sanshin, an Okinawan string instrument, to two eager, respectful young students — Derrick (Eun Ho Lee) and Elmer (Collin Gushiken Hoo) — while David hangs at the edge of the class in the home where he lives with his grandfather. When Sensei isn’t present, the three friends tease one another other, cracking Okinawan jokes.

Costume designer Dusty Behner telegraphs personalities and tastes by dressing Sensei and Elmer in vintage aloha shirts and tidy slacks while Derrick and David strut in baggy, streetwise style (except for David’s sad board shorts).

Excoriated by his grandfather for being a rudderless college dropout, the longhaired David dreams of fame as a rock guitarist or ukulele star but demonstrates little discipline or talent. Complaining to his irate grandfather that traditional music is slow and boring, David says, “Why do Okinawans live so long? They gotta. Otherwise no can finish one dance.”

Sensei favors the ingratiating Elmer, provoking David to cry out, “Grampa, how come the spotlight’s never on me?” (He doesn’t yet see that it actually is.)

Providing consolation and listening to David’s confidences is Ghost of Mom (Serina Dunham), one of Tonouchi’s loveliest creations. This slender, beautiful young woman appears periodically to the tinkling of bells and never says a word, but gives wonderfully expressive frowns and smiles and occasionally breaks into a rhythmic Okinawan dance.

She raised David as a single mother, and the sweetest scene in the play is between the two of them as he reminisces about how, unable to afford a baby sitter, she took him with her on weekends, the two of them chatting in the car, side by side, as she drove her rounds as a pharmaceutical rep.

Other charming scenes involve the chemistry and playful banter between David and Maria (Maile Kapuaala), the Okinawan daughter of an old friend of Sensei’s who comes to board with them while attending the University of Hawaii. As David tries to teach her English and local humor, Kapuaala’s Maria — who proves a quick-witted study — alternates between goofy/bashful and a fierce “Jedi knight” face: She is a defender of peace, indigenous culture and the filial respect that she feels David lacks.

Under the graceful direction of Reiko Ho, all of the young actors are impressive and convincing, and Goo, a sanshin student of Okinawan descent, plays the instrument capably. But it’s the veteran Bento who commands the sparsely furnished stage. The deep-voiced, glowering Sensei seems to be the moral compass of the play, but, as David will learn, things are not so simple.

Frustrated by David’s lassitude, Grampa quits teaching and turns to cards and drinking, leading David to complain, “How come you just lying around? Who you think you? Me?”

As Sensei and Maria speak about Okinawa, parallels are drawn, sometimes with too heavy a hand, between the occupation of Okinawa and Hawaii by the American military and tourism. Maria laments the near disappearance of Uchinaaguchi, and David draws a connection to a Hawaiian language that is now being reclaimed.

At times the talk gets overly expository, and didacticism slows the action. Theater does better when it entertains and leaves the lectures to the academics. At other times things get a bit too cute and sentimental, but that’s forgivable in light of Tonouchi’s exuberant affection for his characters and culture.

In the play’s climax the young people perform a concert for peace, melding hip-hop, Okinawan and Hawaiian elements. A reinvigorated David performs an original Jake Shimabukuro tune, which the musician composed for the play, on the sanlele, a composite of the sanshin and ukulele.

Throughout, the characters speak in pidgin, a composite language that’s a joy to hear. Despite some awkward pauses between lines on opening night, “Uchina- aloha” is a well-paced, funny, touching play that blends cultures, languages and music to make something youthful and new.