A glimpse of some of those who died:
She beams in snapshots. Her enthusiasm and cheer was evident. She was doing, those who knew her say, what she loved.
And now, Victoria Soto is being called a hero.
Though details of the 27-year-old teacher's death remain fuzzy, her name has been invoked again and again as a portrait of selflessness and humanity among unfathomable evil.
A cousin, Jim Wiltsie, told ABC News that investigators informed his family she was killed while shielding her first-graders from danger. She reportedly hid some students in a bathroom or closet, ensuring they were safe.
"She was trying to shield, get her children into a closet and protect them from harm," Wiltsie told ABC. "And by doing that, put herself between the gunman and the children."
Photos of Soto show her always with a wide smile, in pictures of her at her college graduation and in mundane daily life. She looks so young, barely an adult herself. Her goal was simply to be a teacher.
"She lost her life doing what she loved," Wiltsie said.
A year ago, 6-year-old Ana Marquez-Greene was reveling in holiday celebrations with her extended family on her first trip to Puerto Rico. This year will be heartbreakingly different.
The girl's grandmother, Elba Marquez, said the child's family moved to Connecticut just two months ago, drawn from Canada, in part, by Sandy Hook's pristine reputation. The grandmother's brother, Jorge Marquez, is mayor of a Puerto Rican town and said the child's 9-year-old brother was also at the school, but escaped safely.
Elba Marquez had just visited the new home over Thanksgiving and finds herself perplexed by what happened.
"It was a beautiful place, just beautiful," she said. "What happened does not match up with the place where they live."
Dawn Hochsprung's pride in Sandy Hook Elementary was clear. She regularly tweeted photos from her time as principal there, giving indelible glimpses of life at a place now known for tragedy. Just this week, it was an image of fourth-graders rehearsing for their winter concert, days before that the tiny hands of kindergartners exchanging play money at their makeshift grocery store.
She viewed her school as a model, telling The Newtown Bee in 2010 that "I don't think you could find a more positive place to bring students to every day." She had worked to make Sandy Hook a place of safety, too, and in October, 47-year-old Hochsprung shared a picture of the school's evacuation drill with the message "Safety first." When the unthinkable came, she was ready to defend.
Officials said she died while lunging at the gunman in an attempt to overtake him.
"She had an extremely likable style about her," said Gerald Stomski, first selectman of Woodbury, where Hochsprung lived and had taught. "She was an extremely charismatic principal while she was here."
When the shots rang out, school psychologist Mary Sherlach, 56, threw herself into the danger.
Janet Robinson, the superintendent of Newtown Public Schools, said Sherlach and the school's principal ran toward the shooter. They lost their own lives, rushing toward him.
Even as Sherlach neared retirement, her job at Sandy Hook was one she loved. Those who knew her called her a wonderful neighbor, a beautiful person, a dedicated educator.
Her son-in-law, Eric Schwartz, told the South Jersey Times that Sherlach rooted on the Miami Dolphins, enjoyed visiting the Finger Lakes, relished helping children overcome their problems. She had planned to leave work early on Friday, he said, but never had the chance. In a news conference Saturday, he told reporters the loss was devastating, but that Sherlach was doing what she loved.
"Mary felt like she was doing God's work," he said, "working with the children."
Lauren Rousseau had spent years working as a substitute teacher and doing other jobs. So she was thrilled when she finally realized her goal this fall to become a full-time teacher at Sandy Hook. Her mother, Teresa Rousseau, does not hold back when describing what the job meant to her daughter.
"It was the best year of her life," she told the Danbury News-Times, where she is a copy editor.
Rousseau has been called gentle, spirited and active. She had planned to see "The Hobbit" with her boyfriend Friday and had baked cupcakes for a party they were to attend afterward. She was a Danbury native, a graduate of the University of Connecticut and the University of Bridgeport, a lover of music, dance and theater.
"I'm used to having people die who are older," her mother said, "not the person whose room is up over the kitchen."
Connecticut State Police released the complete list of victims killed in the shooting rampage at Sandy Hook Elementary School in Newtown.
Charlotte Bacon, 6
Daniel Barden, 7
Rachel Davino, 29
Olivia Engel, 6
Josephine Gay, 7
Ana Marquez-Greene, 6
Dylan Hockley, 6
Dawn Hocksprung, 47
Madeline Hsu, 6
Catherine Hubbard, 6
Chase Kowalski, 7
Jesse Lewis, 6
James Mattioli, 6
Grace McDonnell, 7
Anne Marie Murphy, 52
Emilie Parker, 6
Jack Pinto, 6
Noah Pozner, 6
Caroline Previdi, 6
Jessica Rekos, 6
Avielle Richman, 6
Lauren Russeau, 30
Mary Sherlach, 56
Victoria Soto, 27
Benjamin Wheeler, 6
Allison Wyatt, 6
To make a contribution to the Newtown Memorial Fund please visit: www.newtownmemorialfund.org