A 16-year-old boy charged with murdering his school principal testified Wednesday that he brought a shotgun and revolver to school not to kill the man, but to make him stop kids from teasing him.

Eric Hainstock is charged with first-degree murder and could face life in prison if convicted. Hainstock shot Weston Schools Principal John Klang on Sept. 29 as Klang struggled to wrestle the gun from the boy.

Prosecutors must prove that Hainstock intended to kill Klang the moment he pulled the trigger. Hainstock's attorneys asked the boy repeatedly if he meant to kill the principal.

"No, I didn't," Hainstock said. "I didn't plan to hurt nobody."

Sauk County District Attorney Pat Barrett claims Hainstock was a bully himself and angry at Klang because the principal twice suspended him in the days leading up to the shooting on the morning of homecoming.

But Hainstock's attorneys contend he suffers from attention deficit disorder, was abused at home and endured endless teasing at school while Klang and teachers looked the other way.

They maintain Hainstock brought guns to school in an effort to make people listen to him. Hainstock attorney Jon Helland said they plan to ask jurors to consider finding the boy guilty of a lesser charge of reckless homicide.

In a flat tone, Hainstock testified he transferred to Weston Schools as a sixth grader. The K-12 schools' building sits in the countryside just outside Cazenovia, about 65 miles northwest of Madison.

Kids there stuck his head in the toilet, stuffed him in lockers, threw him in the bushes and called him names, he said.

Klang started as principal when Hainstock was a seventh-grader and became a confidant, Hainstock said. But Klang didn't stop the teasing, the boy said.

Morgan Gudenschwager, Hainstock's friend, testified Wednesday that he and Hainstock complained to Klang about teasing 20 or 30 times while they were in middle school, but nothing changed.

Hainstock, then a 15-year-old freshman, was about to drive the family's truck to school because he missed the bus. He grabbed a shotgun from his father's gun cabinet and a .22-caliber revolver from his father's bedroom and loaded them, thinking that if people were scared, they'd listen to him.

Helland asked why he loaded the weapons.

"I don't know," he replied. "Just a reaction."

He told everyone in the school entrance, "Everybody get in the (expletive) office. I'm not (expletive) kidding. This is serious."

A janitor tore the shotgun away from him. Hainstock said he spun away, pulled out the revolver and cocked it. He wanted to make people think he was ready to shoot so they would "clear out."

He told Klang to go in the office to talk. He turned around and Klang jumped him, wrapping him in a bear hug and tugging at his gun arm.

Hainstock initially told police he fired all three shots on purpose, but testified he only said that because he was scared during the interview with detectives and knew he had done a terrible thing. He said the first shot was an accident.

After that he "freaked out" and fired again, this time on purpose, hoping to hit Klang in the arm and make him let go.

The gun went off a third time during the struggle, he said.

"The blood was falling on me and stuff like that," Hainstock said. "I'm in shock ... I didn't think Mr. Klang was going to die. I hoped not."

In her cross-examination, Barrett did not ask Hainstock about the day of the shooting. Instead, she rattled off a number of things Hainstock was accused of over the years, including calling teachers names, knocking a student's tooth out, and snapping another student in the head with a rubber band. He agreed the incidents happened.

Closing arguments were expected Thursday.