In a surprise move, Micah Lasher announced today that he’s leaving StudentsFirstNY, an education advocacy organization he helped launch less than a year ago to sway mayoral candidates on education policies.

The news broke first early this morning in the Daily News, and it apparently was such a surprise that even Lasher’s staff at StudentsFirstNY didn’t know about it, sources told GothamSchools. Staff put out a press release shortly after that, naming a temporary replacement and praising Lasher for his.achievements. But questions remain about the group’s future.

Lasher, a “wunderkind lobbyist” with expertise in education policy, spent four years advancing the Bloomberg administration’s agenda before leaving city government last year. He’s returning to public service as chief of staff for Attorney General Eric Schneiderman after a year in charge of New York’s state branch of Michelle Rhee’s national StudentsFirst organization.

Lasher was hired by Rhee and the group’s influential board to lead a well-heeled fight against the city teachers union and its allies during the upcoming mayoral election. At its launch, it pledged to raise $10 million in five years and use its resources to push candidates to declare their positions on thorny education issues, including school closure and charter school co-location policies.

In its first year, StudentsFirstNY emerged as the main — and perhaps only — education advocacy group to aggressively push for those policies, which Bloomberg has embraced during his time in office. But Lasher’s group focused much of its energy and resources on other issues that popped up over time as well.

It gave money to state legislators, published reports, and backed Campbell Brown in a public spat with union leaders. The group also organized parents and pressured the union to negotiate a teacher evaluation system. That effort was unsuccessful, but the group took some credit for recent changes to the state’s teacher evaluation law designed to address issues that led negotiations to fall apart in January.

But with several months still to go before the Democratic primary, it’s unclear how much traction the group gained. Union-backed coalitions have been more successful at getting the attention of the mayoral candidates so far, and some of them have rejected StudentsFirstNY entirely.

Lasher’s departure immediately cast an uncertain future for the organization.

In addition to Lasher’s departure, StudentsFirstNY’s leadership was already in a state of transition. Anna Hall, a former teacher and principal hired this summer, left in February to take a job at Springpoint, a project funded by the Carnegie Corporation that will begin working with school districts to open new high schools. Hall did not respond to requests for comment.

Glen Weiner, who was hired as deputy executive director in July, was named interim executive director. In statements, several members of StudentsFirstNY’s high-profile board of directors  — Rhee, Joel Klein, Paul Tudor Jones, Dan Loeb — applauded Lasher’s first-year accomplishments.

“Micah has been a strong partner and a potent asset for the StudentsFirstNY team,” said Klein, former city schools chancellor. “While we will miss his vision and his passion, StudentsFirstNY is well-positioned thanks to his efforts to continue to fight aggressively on behalf of New York’s students.”

In a statement, Lasher expressed confidence that StudentsFirstNY would handle the transition well.

“I am confident in our team of talented student advocates — in their passion and their ability to realize our mission,” Lasher said.

Lasher was well-liked in political circles, even by some of those who disagree with the causes he advanced.

“I am happy for the enormously talented @MicahLasher,” tweeted City Councilman Mark Weprin, who has sued the city over its charter school co-location policies.  ”Maybe now he and I can go back to agreeing on things.”