More than a dozen supporters of the family attended the hearing, many of them bemoaning a process they said is at odds with the district’s stated goal of reducing the disproportionate number of students of color who are suspended or expelled. Dereian is black, and his race figured into some of the testimony.

“He was a model student,” said Lamark Shackerford, a school district employee who worked with Dereian for two years at Thoreau Elementary School in a program designed to empower young African-American students.

Shackerford said Dereian had a very positive influence on the boys around him and that expelling him would “be a travesty” because it could reverse what appears to be a positive trajectory.

But district officials said Dereian made a serious mistake by bringing a BB gun to school, an error of judgment that endangered the health, safety and property of others.

In testimony Monday, Hong Tran, an assistant principal at Cherokee, said he began investigating the situation the week of Nov. 2.

The previous Friday, a teacher reported that she had observed a student point a gun at another student across from the school and after classes had let out.