A teacher chimes in

• Nikki Giovanni talks to CNN about her former student Cho Seung-Hui.

Professors and classmates were alarmed by his class writings — pages filled with twisted, violence-drenched writing.

"It was not bad poetry. It was intimidating," poet Nikki Giovanni, one of his professors, told CNN Wednesday.

"I know we're talking about a youngster, but troubled youngsters get drunk and jump off buildings," she said. "There was something mean about this boy. It was the meanness — I've taught troubled youngsters and crazy people — it was the meanness that bothered me. It was a really mean streak."

Giovanni said her students were so unnerved by Cho's behavior, including taking pictures of them with his cell phone, that some stopped coming to class and she had security check on her room. She eventually had him taken out of her class, saying she would quit if he wasn't removed.