The Montgomery County school system should share the blame for the death of a 15-year-old boy in a landscaping accident last month, Latino advocates and family members said yesterday, detailing how his mother tried unsuccessfully for four months to enroll the boy in school.

"We are demanding a full investigation into the Montgomery County schools' treatment of Michael Barrios and his sister," declared Gustavo Torres, executive director of CASA of Maryland. He spoke into microphones under a tree at the edge of the Wheaton High School campus, surrounded by television cameras and friends of Michael's family, holding signs in Spanish that translated to "Children Belong in School" and "We Must Care for Our Children."

At times, the roar of school buses, arriving to take children home from the last day of school, drowned out the words of Torres and other speakers.

Michael should have been one of those children, Torres said, but rigid residency requirements kept him -- and scores of other foreign-born students -- from enrolling in classes. He found a landscaping job instead and, within two weeks, died after becoming entangled in a mulching machine.

Kate Harrison, spokeswoman for the county schools, said yesterday that school officials "are looking in great detail into the experience the family had . . . and at this point we can't really comment on exactly what happened."

Michael's cousin, Edgar Trujillo, who graduated from Wheaton High a week ago, said he had had to wait six months before he could go to school, which he described as "a very hard experience."

"I felt as if all my dreams were destroyed," said Trujillo, 20, wearing a T-shirt with a grinning picture of Michael Barrios and the sentiment "We miss you Michael" in Spanish.

Trujillo was on the honor roll, played varsity soccer, won first prize in a theater festival and was captain and Most Valuable Player of the volleyball team. In the fall, he will attend Montgomery College and study international relations, he said yesterday.

"If the school had never received me, I would not have achieved all these accomplishments," Trujillo said. He added that for his family, friends, future immigrants and, most importantly, the memory of his cousin, "I want this to change."

Michael Barrios was born in the United States but had been living in Guatemala until Christmastime. After his arrival in this area, his mother, Nidia Villeda, made repeated trips to the school district's International Students Admissions Office to enroll him and his 11-year-old sister in school, family members said.

Immigration status was not an issue: Michael was a U.S. citizen by birth, and the school office does not seek proof of legal residency. Rather, it was a question of proving that the family lived in Montgomery County. Villeda had a scattered record of their addresses: She moved in January from one place in Montgomery to a house rented by her brother, with his name on the lease and all utility bills; and the address changes on her cell phone bill and bank statement took several weeks to process and, in the meantime, could not be used as proof of residency. Getting to the schools office also required Villeda to forego a day of work.

Throughout the process, family members said, her children stayed home for months, alone, bored and depressed.

Even when a friend and lawyer, Chevy Chase resident Jenny Pensler, got involved, the school system did not budge, Pensler said. Villeda finally showed the school system a copy of the lease, and had her brother go with her to the schools office to sign a notarized affidavit that she lived there, but the final page of the lease was missing, Pensler said.

The school system said that "a complete lease was required and there was no other way to satisfy the residency requirement," Pensler recalled yesterday.

Villeda has returned to Guatemala to bury her son.

County Council Vice President Tom Perez (D-Silver Spring) said in an interview yesterday that he was concerned about the case.

"People come here for a better life, and they don't expect to go home a few months later in a casket," Perez said. "I have questions about why he wasn't in school, and I'm looking forward to getting answers about why that was the case."

"We need to be mindful of what the Supreme Court said: We have a duty to educate every kid, K through 12, who is living here."

Karina Villeda, a cousin of Michael Barrios, joined a protest where speakers chastised the school system for not enrolling the 15-year-old.