NEW YORK >> Benjamin Kwon does not look like a gladiator, but you should see him play the Fried Liver Attack, a wildly aggressive chess opening that wages an all-out assault on the opposing player’s king. The opening is not for the fainthearted.

On a recent Friday afternoon, he beamed as he rattled off the first moves for both sides: pawn to E4, pawn to E5, bishop to C4, and so on, until he got to the real moment of attack, knight to G5. This is where the Fried Liver Attack gets hairy. “Nothing can block it,” he said, his face lighting up.

Benjamin Kwon is 6 years old.

We were sitting in small wooden chairs at Public School 77, the Lower Lab School, a school for gifted and talented students in Manhattan. “Sitting” might be an imprecise word for Ben’s state of constant up-and-down motion.

Last month, Lower Lab’s team of kindergartners and first graders finished first in the state chess tournament, defeating elite private schools like Dalton and Avenues: The World School. Earlier in the school year, a Lower Lab team of first graders won the national championship for their grade. The next national tournament is in May.

For Ben, a first-grader who did not go to the nationals, the state tournament in Saratoga was a weekend to remember.

“The team trophy was taller than me,” he said, almost jumping out of his seat. “The dinner place was so yum — Applebee’s. The first thing you got was nachos.”

Chess is enjoying a boom in New York, and much of it is because of schools like Lower Lab, which have brought the game to very young players, often as part of the regular curriculum. Educators cite research showing that chess helps students develop analytical thinking, set goals, concentrate for extended periods and learn to delay gratification.

“It gives them a different way of using their brain,” said Sandra Miller, the principal at Lower Lab, where every student gets 10 weeks of chess in kindergarten. “It’s an amazing opportunity for them to challenge themselves. With gifted and talented students, sometimes kids get bored with classes, because the work comes so easy for them.”

For Ben Kwon, the appeal was simple. “I really got excited because all my friends were playing chess,” he said.

For schools, chess is also cheaper than sports that require outdoor fields or a lot of equipment.

On a Friday this month, about 70 students from Lower Lab swarmed the weekly after-school session taught by instructors from ChessNYC, a for-profit company that runs programs in 40 New York school.

Spring was beckoning outside, but the children did not seem to notice. Logan Brain, 26, an instructor, rehashed a game from a recent adult tournament and asked the students what moves each player should make.

Ian Buchanan, a third-grader, suggested an unorthodox move, which Brain questioned. “That’s a Karjakin move,” Ian countered, referring to Sergey Karjakin, a Russian player who at age 12 became the youngest grandmaster ever.

The name drew respect in the room. Karjakin, now 26, will play the current world champion, Magnus Carlsen, 25, in the World Chess Championship in New York City this November. It is the first time the championship tournament will be played in New York since 1995.

Ian is one of the top players at Lower Lab, but he was recently passed by his younger brother, Royal, a first-grader, who fidgeted in front of him. Royal is among the best 6-year-olds in the country. The brothers’ success has surprised their mother, Li Xiao, a portfolio manager at Citigroup.

“My husband and I don’t know chess at all,” she said.

The game has also been a window on their characters.

“You see their personality, how they deal with the problems, and the stress,” she said. “Royal is fine with losing. He doesn’t cry. I wonder at this age if they get nervous. I haven’t seen it that much. They don’t realize the situation yet.”

Royal sometimes gets restless in his classes, but can sit for hours at a time over a chessboard, his mother said. “It’s the only activity he can focus on,” Xia said. “He goes to tournaments, and sometimes the game goes on for two hours. I’m surprised he can sit, but he does.”

During a break, Royal answered questions distractedly, staring at his fingers as if contemplating future moves. Like his teammates, he readily cited his chess rating, a figure that changes each time a player wins or loses in a tournament. Players monitor their ratings and those of their friends on the website plycount.com. At the start of a match, the first question after they sit down at the board is often, What’s your rating?

Since kindergarten, Royal and another boy, Morgan Mairaj, have leapfrogged each other as the team’s top player, with ratings climbing above 1,300, or twice as high as most of their teammates. Players raise their ratings by beating higher-rated opponents, but fall back if they lose to opponents with lower ratings. At tournaments, players are grouped according to their ratings. Royal said his goal was to top 1,800 by the end of the year.

“Magnus Carlsen is 1,500 higher than me,” he said. (It should be noted that Carlsen is the highest rated chess player in history, at 2,863. Bobby Fischer never broke 2,800.)

For parents, the numbers are a mixed blessing. “The coaches and parents hate it, but kids absolutely love it,” said Peter Marinis, who has two sons playing on the team, and a third coming up behind them. “They’re like, Dad, what’s my score? I never knew they were so competitive.”

For competitive players and their families, the game is demanding. There’s a tournament somewhere in the city every week or two, typically lasting all day; parents from Lower Lab drove to Saratoga for the two-day state championships, and to Nashville, Tennessee, last year for the nationals. Brain assigns 50 chess puzzles weekly as homework. Then there are pickup games or Saturday lessons at the Chess Forum, a store in Greenwich Village, or at the tables in Washington Square Park.

“These kids are very committed, and if you’re not committed, it is very difficult to stay at the top echelon,” said Ashar Mairaj, the father of Morgan and an older daughter Momoca, who is also one of the school’s top players. “You have your puzzle set every day. You play with your sibling every day. You have a tutor that comes once a week and teaches you strategy. Every day you have a regimen.”

The game can also be expensive. At Lower Lab, fees for the after-school program top $500 a semester, which helps pay for the teachers from ChessNYC. Tournaments run about $40 per student; travel costs are extra. The school and PTA pay for kindergarten instruction run by ChessNYC, and parent volunteers run a lunchtime chess club for girls, formed to address the shortage of girls in the competitive ranks.

“It’s a really big commitment,” said Amy Gillston, a child therapist, whose first-grade son, Noah, attends Lower Lab. “Some of these private schools, they spend on private coaching with the best of the best. All of us agree that we’re only doing this while it’s fun.”

Recently, Davin and 28 other Lower Lab players made their way to the Avenues school for their first major tournament since winning the state championships in Saratoga. The tournament brought together students from 65 area schools, and had to turn students away after filling its 250 slots. Boys outnumbered girls by about four to one. Pandemonium and sugar intake swelled the halls, only slowly giving way to chess.

Peter Marinis and his sons arrived at 9:30 a.m., after 8 a.m. baseball; later, they had a birthday party to attend.

For parents, the tournaments are an endurance test, often lasting eight hours. In contrast to sporting events or dance recitals, junior chess tournaments typically do not allow parents into the rooms where the children play, so they waited in a team room, learning the results only when the children returned between rounds to go over their games wit Brain.

“It’s stomach-churning,” said Mairaj, waiting for the results of his children’s games. “It’s never boring. How can something that gives you anxiety be boring?”

The Lower Lab team got off to a rocky start, with the first three players losing their first games.

Marinis’ son Rylan, 6, slumped toward the paper score sheet and wrote a zero to announce his loss. “High-five,” Marinis said. “Win or lose, it’s always high-fives.”

Then Ben Kwon posted the team’s first victory. He played an opening similar to the Fried Liver, but not exactly, he said, and beat an opponent rated higher than he was. He sailed across the room to his mother, Michelle Park.

Seven hours into the tournament, families in the less advanced groups — whose games tend to be shorter — were making their way out into the late-afternoon sunshine. Xiao awaited the return of her two sons, whose games were still in progress. “Now’s the real work,” she said: cooking dinner for five, supervising Sunday night homework and maybe stealing a quiet moment with her husband. “Then I clean up and get to bed at 12 o’clock, basically.”

Monday morning everything would start up again — the tutors, the chess puzzles, the competitive games between siblings. And in less than a month, some will go to the national championships in Nashville.

Marinis, who is planning to fly to Nashville this year (last year he and others drove), was bound for ice cream and the birthday party, his three sons in tow. His older son, Pearce, had won three of his four games, raising his rating to a tantalizing 999.

“I use these as lessons for homework,” Marinis said of the tournament. “I say, ‘If you can do what you did on Sunday, look, this math is not going to be a problem.’”