Leonard Villanueva had to find a way to make the pig more likable.

The main character in his children's book "The Hungry Pua'a and the Sweet Sweet Potato" does some unlikable things before he learns his lesson about sharing. Villanueva had to make sure kids would like the character enough to stick with the story to the end.

So he based his illustration of the pig on his brother Marc's kindergarten picture.

Sure enough, if you look at the wide, self-satisfied grin on that pua'a's face, the "rascally charm" of a little boy posing for his school picture comes through.

"My brother cracked up when I told him," Villanueva says. Brother Marc is grown, an artist living in Atlanta. "He said, 'That's wonderful!' "

Leonard Villanueva is a teacher at Honowai Elementary School in Waipahu. For years, he'd read stories to his pupils and think, "I could have written that."

After winning the prestigious Milken Family Foundation National Educator Award in 2002, Villanueva put his "could have" into action. He wrote and illustrated "Kaipo & the Mighty 'Ahi," a story painstakingly researched and polished and meant for teaching, among other things, rhetoric to upper-elementary pupils. That book was published by Beach House Publishing in 2004. The story of the pua'a, targeting a younger audience, came out a year later.

In both books, Villanueva manages to blend his mission as a teacher, his love of art and the practical demands of a children's book into truly good stories. There's nothing forced or commercial or heavy-handed. These are fun, sweet books.

"If you read 'Kaipo,' there's really an overload of rhetorical devices in the text," he says. "Things like personification, onomatopoeia, simile and metaphor."

The idea was to teach all these lessons in one book, along with touches of history, science and culture, because textbooks are so prohibitively expensive. "This way, it saves money and saves time."

"The Hungry Pua'a and the Sweet Sweet Potato" was inspired by Villanueva's childhood experiences growing up in Pearl City as No. 4 of 11 children.

"It's the values our parents taught us. With so many wants, so many needs, you learn you have to share," he says.

The text uses repetition and rhyme, techniques meant to foster reading skills in young children. Villanueva reads the book to his older pupils as well.

"The older students will ask things like 'Isn't there supposed to be a comma after the first sweet?' and that leads to discussions of parts of speech. We talk about how sweet potato is a noun and the first sweet is an adjective."

Each picture in the book takes Villanueva up to two weeks to finish. He developed a technique of using his fingertips to apply oil pastels to the paper to give the animals a softer, fuzzier look. Oil pastels can be smudged and softened, but not erased. The color is somewhat forgiving, but never forgets. He points to a picture in "Kaipo."

"See that? I dropped a crayon on the picture so I had to draw a rock there to cover up the mark."

He uses pieces of card stock to shape the edges of the figures and takes great care in researching and properly depicting native plants and the landscape of actual Hawai'i beaches.

Villanueva says he's still surprised to pick up a book with his own name on the cover; and when he reads the story to the pupils, discussing the "author's message" is funny when he himself is the author.

He has also enjoyed the insight that children have had into his work, picking up on his themes and adding some of their own.

"They identify with the pua'a," he says. "They know him, and he doesn't share his crayons."

Some kids have said the theme of the story is about sharing and second chances. Others have more pragmatic interpretations.

"One student said the theme was, 'If you're not going to share something, eat it in the corner.' "

Lee Cataluna's column runs Tuesdays, Fridays and Sundays. Reach her at 535-8172 or lcataluna@honoluluadvertiser.com.