When you’re passing through the metal detector just inside Liberty High School’s classroom 104, all the chess boards might catch you a little off guard.

Teens stationed at their desks bent over bishops, knights and rooks are deep in concentration.

Clearly, chess is taking over Sean King’s Liberty High classroom.

“I think the staff here are happy to see them excited about something so positive,” King said. “It’s brought the kids together.”

The chess action is a trend sparked by King, an instructor focused on getting students at both Liberty and Chamberlain high schools fired up about the strategic game. A student tournament wrapped up Halloween week, and Daniel Lueras — a 15-year-old Chamberlain sophomore — emerged as champion.

Quiet and cautious, Lueras takes his newfound status in stride.  He is one of the Napa County Office of Education’s 200-plus court and community school students, some of whom have pasts in the criminal justice system or are otherwise unable to attend traditional schools.

Lueras, a man of few words, has only basic tips for those who want to improve their chess game.

“It takes practice,” he said.

Students from one Chamberlain class and four Liberty classes participated in the tournament, which produced three finalists in addition to Lueras — a champ who also admits a penchant for paintball.

Another finalist emerging from a 32-player field was Gary Dent III, a junior at Liberty who won second place.

Dent, 17, said the game shows the mettle of students at Liberty and Chamberlain.

“Some may think that we’re troublemakers, but it’s a learning experience,” he said. “People think that we don’t think and we act on impulse. But you can’t act on impulse in chess.”

Chess, he said, requires players to adapt and think on their feet.

“You gotta be two steps ahead,” he said. “You’ve got to look beyond your next move.”

Other Liberty students are adept at the game. During practice games and up until the tournament’s close, Dent was often tied with finalist AJ Austin, according to King.

Austin, 16, said the key is keeping your strong pieces on the board. “The less the sacrifice, the more chance you have to win.”

Student Jessica Estrada is learning the ropes. At 16, Estrada is the only female in King’s class who took part in the chess tournament and she’s now surpassing male players. She has placed third overall in King’s class so far.

“I just learned how to play two weeks ago. ... Some people take it so serious,” she said, adding that because losing is also part of the game, it’s important to roll with the punches.

For King, chess plays other roles, drawing out teens who otherwise barely acknowledge each other.

Touting the “community-building” interactions teens took from the chess tournament, King said he hopes to expand the competition next year to students at Wolfe High School, Crossroads School and other county office-run campuses.

“I think they’ll be receptive,” he said.