A 16-year-old Harding High School student told St. Paul police he brought a loaded handgun to class Wednesday to protect himself from a gang.

Nu Kenji Lo pleaded guilty Thursday in juvenile court to felony possession of a dangerous weapon on school property, the Ramsey County attorney’s office said. Prosecutors dropped a petty misdemeanor charge of marijuana possession.

According to prosecutors, Lo was sent to an assistant principal’s office Wednesday after a teacher smelled marijuana on him. When Lo admitted having marijuana in his backpack, the principal searched it and found the drugs and a loaded .22-caliber handgun wrapped in a T-shirt.

Lo apologized and agreed to talk to a police investigator at the East Side school. He said he knowingly brought the marijuana and handgun to school in his backpack. He said he associates with the “AC” gang — an apparent reference to the Asian Crips — and brought the gun because he felt threatened by other gang members.

Police discovered the gun had been reported stolen in Green Bay, Wis. Lo said he found the gun two months ago in some weeds along Payne Avenue.

Lo will be held at the Juvenile and Family Justice Center until his dispositional hearing, set for Nov. 5.

Aside from criminal penalties, the crime could make Lo the first St. Paul Public Schools high school student in several years to be expelled.

School district officials aren’t saying how they will discipline Lo. But according to state law and district policy, a student who brings a gun to school will be expelled for at least one year, unless the school board decides otherwise.

The district hasn’t expelled a high school student in at least five years, according to a discipline report officials released Wednesday. That data showed St. Paul high schools have logged about 14 reports of violence per week over the past three full school years.

Those incidents include mostly fights but also assaults and the presence of weapons. The number of students involved in that behavior ranged from a five-year high of 686 in 2010-11 to a low of 599 in 2013-14.

Although the number of violent incidents recorded has been fairly steady, students have been punished less harshly in recent years.

In 2010-11, 87 percent of students caught fighting received an out-of-school suspension. That figure has dropped to between 66 percent and 71 percent each of the past three years as schools increasingly have turned to short-term dismissals of one school day or less.

Of the 508 high school students caught fighting last school year, 351 were suspended from school; 111 were kicked out of class for a day or less; five got in-school suspensions; and 41 received some other disposition.

Donna Yu, who teaches at Highland Park Elementary, said consequences for students seem to vary widely depending on the school. At Hazel Park Preparatory Academy, where she taught last school year, she said “students were not held accountable for their actions” and they acted like it.

Yu requested a job transfer after she was caught in the middle of a fistfight between two fifth-grade girls near the end of last school year and suffered a concussion, she said. She was on the ground for perhaps two minutes while the girls continued to fight on top of her.

“I kept saying, ‘You are not punching her. You are punching your teacher,’ ” she said.

The school district Wednesday acknowledged a spike in fighting this week, including six fights in three days at Como Park Senior High. Officials said they would work with police and other community partners to address behavioral problems.

The Rev. Runney Patterson of New Hope Baptist Church wants parents to take control of their kids. He’s involved with the St. Paul Black Interdenominational Ministerial Alliance, one of the groups working with the school district.

“A lot of the responsibility is not necessarily on principals, teachers and staff,” he said in an interview on student discipline last month. “I think a lot of the responsibility goes back on the mother and father.”

Mary Mackbee, Central High School’s longtime principal, said Wednesday that kids are needier than they used to be and less equipped to work out their differences.

“With this whole advent of social media, kids really don’t communicate with each other one on one. It’s a lot of texting. It’s a lot of taunting back and forth, which really just increases the amount of animosity that comes back to us,” she said.

Mackbee added that students are recording the school fights with cellphones, making a spectacle of the violence.

A Central student who didn’t want his named used for this report recorded several teenage girls fighting recently and posted it to Facebook.

He said gangs have to do with some of the school-related violence. In other cases, he said, friends turn against each other over things posted on Facebook.

“The kids is angry,” he said. “The kids feel like they got nobody that cares about them, so they go to school and act a fool.”

Josh Verges can be reached at 651-228-2171.

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