Just days into the 2013 legislative session, state lawmakers have introduced a measure to undo Mayor Bloomberg’s signature educational achievement: mayoral control of the massive New York City school system, The Post has learned.

Bloomberg has used the sweeping power to implement accountability and innovations — often over fierce opposition from entrenched interests.

These include tightening “social promotion” from grades 3 to 8, adopting a new school grading system, extending the school day for struggling students, and dramatically expanding choice and opportunity through charter schools and other alternative schools.

The bottom line: During Bloomberg’s tenure, the high-school graduation rate has substantially increased, supporters said.

But lawmakers pushing the bill to kill mayoral control counter that Bloomberg and his chancellors have run the schools like autocrats.

“The school system needs to be restructured. There is less community and parental input under mayoral control. There’s got to be a way to give parents more say in their children’s education. They don’t have that now,” said Assemblyman David Weprin (D-Queens), who is sponsoring the measure.

The proposal would strip the mayor of appointing the majority — eight of 13 appointees — to the Panel on Education Policy, which replaced the Board of Education.

Under a reconstituted board, the mayor would have only four appointees. Each of the five borough presidents would have an appointee and the City Council would have four appointees.

And the board, not the mayor, would have the authority to hire the schools chancellor.

The mayoral-control law is not up for renewal until June 30, 2015. But the bill advanced by Weprin and state Sen. Velmanette Montgomery (D-Brooklyn) is an early bid to sway public opinion for what could be a bloody political battle.

Weprin said the United Federation of Teachers — which has resisted some of the reforms — is “very sympathetic to changes” and “happy that there’s a discussion on mayoral control.”

And the effort to scuttle mayoral control comes amid a heated mayoral race this year to replace Bloomberg.

“This measure has failed time and time again, and we are confident it will follow suit this year,” said Bloomberg spokesman Mark Botnick.

ccampanile@nypost.com