Teachers at a small charter school in Brighton, Massachusetts, have decided to unionize under the American Federation of Teachers union, the Boston Globe reports. The teachers reportedly had complaints about management — which is interesting also because the school leader, Diana Lam, appears to be the same Diana Lam who was ousted as Joel Klein’s first deputy chancellor in a nepotism scandal.

This is a clear victory for the AFT, which has been campaigning to bring charter school teachers under its fold in New York and nationally. But is it a loss for the charter school world and, more importantly, for children?

Charter leaders in Massachusetts are reacting with vocal concern, much more than I saw raised here when a few charter schools unionized. Here, charter leaders have quietly sought to counteract union efforts to organize teachers, offering information on the downsides as well as the up-sides of unionization, but supporters have also welcomed warmly a unionized charter school, Green Dot, to the Bronx.

The Globe quotes the school’s board chairwoman, Stephanie Perrin:

“They have every right to unionize and . . . support their best interests,” Perrin said. But “we have a responsibility to not only support their interests but those of the school’s families and students.”

Perrin said she worries the teachers will seek a contract with so many work rule restrictions that it would not allow for enough freedom for the school to run as a charter.

And a charter school association leader:

The state’s charter school association yesterday downplayed the latest development, characterizing it as an isolated incident at a school plagued with high turnover among its administrators and faculty.

Nevertheless, the association acknowledged the development could represent a major setback for its movement if teachers at other charter schools unionize too. The association contends that popular union contract work rules – governing everything from length of school day to employee termination procedures – strangles educational creativity, leaving administrators with less flexibility, especially when they want to quickly execute new programs or institute new policies.

“The big question on the table is, what is the motive of the [federation of teachers] . . . is this an attempt to kill charter schools?” asked Marc Kenen, executive director of the Massachusetts Charter Public School Association.