He had just explained to Polanco and his history classmates at Virgil Middle School in Koreatown why he had been absent: He had been in the hospital after an attempt at suicide.
Polanco looked at the cuts and said they "were weak," according to witness accounts in documents filed with the state. "Carve deeper next time," he was said to have told the boy.
"Look," Polanco allegedly said, "you can't even kill yourself."
The boy's classmates joined in, with one advising how to cut a main artery, according to the witnesses.
"See," Polanco was quoted as saying, "even he knows how to commit suicide better than you."
The Los Angeles school board, citing Polanco's poor judgment, voted to fire him.
But Polanco, who contended that he had been misunderstood, kept his job. A little-known review commission overruled the board, saying that although the teacher had made the statements, he had meant no harm.
It's remarkably difficult to fire a tenured public school teacher in California, a Times investigation has found. The path can be laborious and labyrinthine, in some cases involving years of investigation, union grievances, administrative appeals, court challenges and re-hearings.
Not only is the process arduous, but some districts are particularly unsuccessful in navigating its complexities. The Los Angeles Unified School District sees the majority of its appealed dismissals overturned, and its administrators are far less likely even to try firing a tenured teacher than those in other districts.
The Times reviewed every case on record in the last 15 years in which a tenured employee was fired by a California school district and formally contested the decision before a review commission: 159 in all (not including about two dozen in which the records were destroyed). The newspaper also examined court and school district records and interviewed scores of people, including principals, teachers, union officials, district administrators, parents and students.
Among the findings:
* Building a case for dismissal is so time-consuming, costly and draining for principals and administrators that many say they don't make the effort except in the most egregious cases. The vast majority of firings stem from blatant misconduct, including sexual abuse, other immoral or illegal behavior, insubordination or repeated violation of rules such as showing up on time.
* Although districts generally press ahead with only the strongest cases, even these get knocked down more than a third of the time by the specially convened review panels, which have the discretion to restore teachers' jobs even when grounds for dismissal are proved.
* Jettisoning a teacher solely because he or she can't teach is rare. In 80% of the dismissals that were upheld, classroom performance was not even a factor.
When teaching is at issue, years of effort -- and thousands of dollars -- sometimes go into rehabilitating the teacher as students suffer. Over the three years before he was fired, one struggling math teacher in Stockton was observed 13 times by school officials, failed three year-end evaluations, was offered a more desirable assignment and joined a mentoring program as most of his ninth-grade students flunked his courses.
As a case winds its way through the system, legal costs can soar into the six figures.
Meanwhile, said Kendra Wallace, principal of Daniel Webster Middle School on Los Angeles' Westside, an ineffective teacher can instruct 125 to 260 students a year -- up to 1,300 in the five years she says it often takes to remove a tenured employee.
"The hardest conversation to have is when a student comes in and looks at you and says, 'Can you please come teach our class?' " she said.