Neighbors knew her from the monthly gathering of women who rotated between homes for games of the dice game bunco. Lanza was an enthusiastic garderer, while poking fun of the fact that few could see the result because her house was set back from the road on a low rise, partly cloaked by trees.

"She used to give me a hard time, you know, because I put out all these Christmas lights, and she said, 'I put out mine, too, but you can't even see them,'" said Rhonda Cullens, who lives one street over.

Lanza also began telling friends that she'd bought guns and had taken up target shooting, John Tambascio said.

All three of the guns that Adam Lanza carried into Sandy Hook Elementary were owned and registered by his mother — two handguns and a .223-caliber Bushmaster rifle, his primary weapon, law enforcement officials said.

Investigators said Sunday that Nancy Lanza visited shooting ranges several times and that her son also visited an area range.

Ginger Colburn, a spokeswoman for the Bureau of Alcohol, Tobacco, Firearms and Explosives, said it's still not clear whether Nancy Lanza brought her son to the range or whether he ever fired a weapon there.

Marsha Lanza told the Chicago Sun-Times that Nancy Lanza wanted guns for protection. "She prepared for the worst," Marsha Lanza told the newspaper. "I didn't know that [the guns] would be used on her."

Guns were her hobby," Dan Holmes, who got to know Lanza while doing landscaping work for her, told The Washington Post. "She told me she liked the single-mindedness of shooting."

Although trips to shooting ranges gave Lanza an outlet, she returned home to the ever-present challenges of raising a son with intractable problems.

At Newtown High School, Adam Lanza was often having crises that only his mother could defuse.

"He would have an episode, and she'd have to return or come to the high school and deal with it," said Richard Novia, the school district's head of security until 2008, who got to know the family because both Lanza sons joined the school technology club he chartered.

Novia said Adam Lanza would sometimes withdraw completely "from whatever he was supposed to be doing," whether it was sitting in class or reading a book.

Adam Lanza "could take flight, which I think was the big issue, and it wasn't a rebellious or defiant thing," Novia said. "It was withdrawal."

The club gave the boy a place where he could be more at ease and indulge his interest in computers. His anxieties appeared to ease somewhat, but they never disappeared. When people approached him in the hallways, he would press himself against the wall or walk in a different direction, clutching tight to his black briefcase.

Marsha Lanza described Nancy Lanza as a good mother.

"If he had needed consulting, she would have gotten it," Marsha Lanza said. "Nancy wasn't one to deny reality."

But friends and neighbors said Lanza never spoke about the difficulties of raising her son. Mostly she noted how smart he was and that she hoped, even with his problems, that he'd find a way to succeed.

"We never talked about the family," John Tambascio said. "She just came in to have a great time."

A report by Associated Press reporter Adam Geller is included in this story.