“What you have to understand is that not all villains are evil.”

That’s the first sentence of all the entries in a teen writing competition hosted by YALLWEST, the young-adult book festival being held this weekend in Santa Monica.

The finalists’ poems and short stories are being judged by a panel of authors from the festival, which is celebrating its second year on the West Coast.

And the awards presentation for the writing contest is one element of a massive event April 30 and May 1 at Santa Monica High School that will unite scores of authors and storytellers with hundreds of literature fans for panel discussions, book signings and other activities.

“We have one mission — to get books into the hands of kids, and to say the words that will get them to open them,” said YALLWEST co-director Margaret Stohl. “We don’t care if it’s a comic book or a graphic novel or Shakespeare. Open a book, open up your world, then go out there and change the story.”

Stohl, a Santa Monica resident, is among the authors changing the story for the young-adult genre. Her book, “Beautiful Creatures,” was made into a 2013 movie of the same name, and she has worked extensively in the video game industry.

Festival co-director Melissa de la Cruz has also found success in the young-adult genre. The acclaimed author’s novel, “Witches of East End,” was adapted into a Lifetime series, and she recently released a book, “The Isle of the Lost,” about the children of famous Disney villains.

Stohl and de la Cruz are two of the 100-plus authors taking part in YALLWEST, which launched last year as a sister festival to the annual YALLFEST in Charleston, South Carolina. The mostly free expo will include 60 panels as well as a variety show, a performance by all-author band Tiger Beat and a Harry Potter cosplay event. The festival website touts it as two days of “general geeky debauchery.”

Award-winning author Rainbow Rowell, who wrote “Carry On: The Rise and Fall of Simon Snow,” will give the opening keynote speech on Saturday. Acclaimed authors Matt de la Peña (“Last Stop on Market Street”) and Jason Reynolds (“All American Boys”) are expected to wrap up the event on Sunday.

This year’s festival will kick off April 29 with a preview night at Santa Monica Public Library’s main branch, 601 Santa Monica Blvd. The ticketed, sold-out event will feature author karaoke as well as games, prize giveaways and food trucks, according to the event website.

Students who entered the aforementioned creative writing contest were asked to submit entries of three pages or fewer in length by April 10. Awards will be distributed in separate age divisions for grades 6-8 and 9-12.

Meanwhile, the book festival is also taking on a philanthropic component through the Purple Ink Award, which allows teachers to apply for money for their classroom libraries. The grant competition was created to support educators in underserved schools who have made sustained efforts to promote literacy.