Students and members of the Hayfield High School community during a candlelight vigil mourning the loss of principal Dave Tremaine on Monday. (Thomas Kinder /PixJrPics.com)

Hundreds of Hayfield Secondary students gathered for a candlelight vigil at the Fairfax County school Monday night to remember Dave Tremaine, who died of cancer earlier in the day — two weeks after he stepped down as principal and the day before graduation ceremonies.

Tremaine, 49, who joined the county school system as a fourth-grade teacher in 1991, had led Hayfield since 2010 and was its biggest cheerleader. He was diagnosed with advanced colon cancer in 2011 and continued as Hayfield’s principal throughout a treatment regimen that included chemotherapy, radiation and clinical trials.

“It’s heartbreaking,” said Fairfax Schools Superintendent Karen Garza.

“He was one of the finest principals I’ve ever had the opportunity to work with. He will be sorely missed, not only by Hayfield Secondary but throughout our entire division.”

Teenagers, dressed in orange Hayfield Hawks T-shirts, consoled and hugged one another during the hour-long vigil in front of the school, which is near Alexandria. As candles flickered in the humid air, students offered their favorite memories of Tremaine, who often roamed the halls with a pet lizard, Vinnie, clinging to his shoulder.

Former Fairfax County schools superintendent Jack D. Dale, left, with Dave Tremaine, who was then principal of Hayfield Secondary School, at the school on Sept. 7, 2010. (Donnie Biggs/Fairfax County Public Schools)

“His absolute favorite thing, and somewhat his regret, was that he felt like he was just getting started there,” said his wife, Robyn. “It was his dream job.”

Many of the students at the vigil were freshmen when Tremaine joined the school, and Tuesday afternoon they earned their diplomas at a graduation ceremony where his absence was palpable.

Senior Erik Kovatch, 18, said he remembered first meeting Tremaine four years ago. Kovatch, a Junior ROTC cadet, was performing push-ups one afternoon when Tremaine got on the ground and started doing the exercise beside him.

“I thought, ‘Who is this guy? He’s crazy,’ ” Kovatch said. “I asked him what he was doing. He replied: ‘Having fun.’ ”

Other students recalled Tremaine donning funky wigs and wearing festive orange-checkered suits to celebrate his Hayfield pride. He gamely participated in a school theater production of “Singin’ in the Rain.”

On Fridays before football games, his voice would come alive on the intercom system as he belted out the school’s fight song.

A strapping 6-foot-5, Tremaine was known to greet students by extending his arms and flapping them like wings to show his allegiance to the Hayfield Hawk mascot.

“Dave was a bright, shining light that brought an amazing spirit of happiness and hope to Hayfield,” said School Board Vice Chairwoman Tammy Derenak Kaufax, whose Lee District includes Hayfield. “The kids loved him, the teachers loved him, and once you met Dave, you could understand why.”

Megan Nugent, a Hayfield theater teacher, said Tremaine helped create a community at the school that made every student, from seventh-graders to seniors, feel welcome.

“The stereotypical idea of high school is that each student finds their one niche,” Nugent said. “He showed the students, ‘You belong here in every corner of the building.’ ”

Mike Lambert, Hayfield Parent Teacher Student Association president, said Tremaine became principal shortly after a boundary change moved a large portion of the student body out of the school, devastating morale. Tremaine’s enthusiasm helped rejuvenate the school, Lambert said.

“He displayed a unique combination of effective leadership and infectious spirit that was unmatched by any administrator before him,” Lambert said.“That deep pride and intense spirit that he cultivated in the Hayfield Secondary community will be his greatest legacy.”

Tremaine, a native of Evanston, Ill., grew up in Rockville and graduated from the University of South Carolina, where he studied finance. He worked in banking in Chicago before deciding to pursue a career in education. He met his wife during their first year teaching at Fairfax County’s Dranesville Elementary.

He later served stints at Luther Jackson Middle School and at Westlawn and Cub Run elementary schools before assuming administrative roles at Lake Braddock Secondary, Glasgow Middle and the Falls Church Academy.

Tremaine, who was absent for much of this school year for cancer treatments, officially stepped down in late May. He died Monday afternoon at the Reston Hospital Center with his wife by his side. Survivors also include his parents, Myron “Dave” Tremaine and Ann Tremaine; a brother; a sister; and three children, Samantha, 19, Grant, 16, and Parker, 10.

His wife said that Tremaine used his cancer diagnosis and treatment as a way to teach his students about persistence through adversity.

“He’d say, ‘I’m still fighting,’ ” Robyn Tremaine said. “It was a big part of who he was and what he wanted to tell the kids.”