EUGENE, Ore. (AP) _ Kip Kinkel, the meek-looking teen-ager who killed his parents and gunned down two classmates at school, abandoned an insanity defense Friday and pleaded guilty to murder in a deal that could someday let him walk free.

The plea bargain came three days before Kinkel was to go on trial in the May 21, 1998, attack at Springfield's Thurston High School _ the third in a string of school shootings that included Pearl, Miss., Paducah, Ky., Jonesboro, Ark., and Littleton, Colo.

``My mind is clear and I am not sick,'' read the text of the plea agreement signed by the 17-year-old Kinkel. He sat slumped in a chair in court and never lifted his head as he read each paragraph silently to himself and initialed it ``KK.''

He pleaded guilty to four counts of murder and 26 of attempted murder.

Kinkel could get as little as 25 years, meaning he could be free by age 42. If he had been convicted as charged, he could have faced life in prison without parole. No sentencing date was set.

Under the agreement, he will get a total of 25 years for the murders. Prosecutors have recommended 7 1/2 years for each attempted murder count for the 25 students he wounded and a detective he attacked with a knife. The judge will decide whether those sentences will be tacked onto the end of the 25-year sentence.

District Attorney Doug Hacleroad called the deal ``the best thing for the community'' and refused to comment on the possibility of a 25-year sentence. He noted that survivors of the attack will get a chance to speak before Kinkel is sentenced.

Because Kinkel was 15 at the time of the slayings, he could not have faced the death penalty.

His lawyers had hoped to spare him a life sentence by proving he was mentally disturbed. If they had succeeded, Kinkel would have been confined to a mental hospital until he was no longer deemed a danger to society.

Kinkel told investigators he had ``no choice'' but to kill because he had embarrassed his parents by getting expelled for having a gun in his locker. He said he thought he was a disappointment to his parents.

``I had to be 100 percent,'' Kinkel told a psychiatrist. ``No one is perfect though. Lots of times, life sucked. With my parents, if I didn't do the best, I was an embarrassment to my parents.''

Kinkel shot his parents in their home. The following morning, he dressed in a trench coat, walked into the cafeteria just before classes and opened fire with a semiautomatic rifle. He squeezed off 50 rounds in 90 seconds, killing Ben Walker, 16, and Mikael Nickolauson, 17.

Several classmates tackled Kinkel as he tried to reload. Later, in a jail interview room, Kinkel lunged at a detective with a knife that had been taped to his leg and begged police to kill him.

Kinkel had managed to convince his parents' friends that he was a good kid. But classmates knew he had bragged about building bombs and torturing animals and voted him Most Likely to Start World War III. Desperate to control his son, Kinkel's father tried counseling and Prozac and even tried to get his son into the National Guard.

At Thurston High on Friday, principal Larry Bentz came over the loudspeaker and announced the plea bargain.

``We were all like, `Shut up,'' said Bekah Snare, 17. ``We don't want to hear about it anymore.''

``I'd kind of like to know exactly why he did it,'' said Tony Case, who was shot in the back and leg. ``We're never going to find out.''