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The gunman who killed 26 children and adults in an elementary school took college classes when he was only 16, a spokesman for Western Connecticut State University said Monday.

Paul Steinmetz, spokesman for the Danbury school, confirmed that Adam Lanza earned a 3.26 grade point average while a student there. He dropped out of a German language class and withdrew from a computer science class, but earned an A in a computer class, A-minus in American History and B in macroeconomics.

He participated when called on by the teacher in his evening course on introductory German, according to Don Stasny, who was one of about a dozen other students in the class in the spring of 2009. She said she and a classmate once invited him out to a bar but he declined, saying he was only 17.

“On one side, he did something unspeakable, but on the other, that’s not how I remember him,” Stansy told CBS News correspondent Seth Doane. “I remember him as the nice kid, you know, I sat near to in class. We’d joke, he’d laugh, that kind of thing.

Stasny said she saw him later when he came in as a customer at a video game store when she was working. She said she shared a laugh with him about how difficult the German class was. She told him she failed one of the exams, and he mentioned he got a D.

“I just remember him as a nice, quiet kid,” she said.

Steinmetz says Lanza was among a small group of 16-year-old among the school’s 5,000 undergraduates.

The Hartford Courant and The Wall Street Journal first reported Lanza’s academic record at Western Connecticut State.

Steinmetz said Lanza took his last class in the summer of 2009 and didn’t return.

Sources told CBS News correspondent John Miller that Lanza had attended Sandy Hook Elementary, the site of the shooting, at one time, but it is unclear when or for how long. Lanza’s aunt, Marsha, told CBS News his mother eventually homeschooled her son after disputes with the local school district.

“[Nancy, Lanza’s mother”] had issues with school…she battled with the school district,” said Marsha Lanza. “I’m not 100 percent certain if it was behavior, learning disabilities, I really don’t know. Bu he was very, very bright. He was smart.”

Nancy Lanza was found dead in the Newtown, Connecticut home she shared with Adam, her youngest of two children. Police believe Adam Lanza killed his mother, and then collected guns registered to her in their home to use in his rampage at the elementary school.

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