ORLANDO, Fla. -- Prosecutors trying the case against accused teen killer Michael Hernandez put a line-up of his former classmates on the stand Friday morning.

They described his actions and appearance in their first period computer class the morning Jaime Gough was killed in a bathroom at Southwood Middle School in February 2004.

They also answered questions that indicated the prosecutor's pre-emptive strike on Hernandez's lawyer's insanity defense.

"Did he ever, in the period of time in that class, act in any unusual or bizarre way that stuck out in your mind?" prosecutor Kathleen Hogue asked one student.

"No," she answered.

Classmates described Hernandez as friendly and sociable, but with a dark side. They remember him enjoying computer sites depicting decapitations and mutilated bodies.

"I walked over and looked and asked him, 'Why do you have that on your computer?'" said former Southwood student Natalie Krakowski. "He said, 'I like it. It's cool. It's really neat.'"

Prosecutors argued that Hernandez, then 14 years old, coldly and calculatingly planned and executed the killing. His attorney, Richard Rosenbaum, argued that same testimony indicates Hernandez was legally insane at the time, and not responsible for his actions.