California teacher unions representing 400,000 instructors are appealing a court ruling which struck down state laws on tenure and other job protections.
The California Teachers Association and the California Federation of Teachers filed the appeal Wednesday in Los Angeles, arguing a judge's decision there last week is riddled with errors.
Gov. Jerry Brown, who has the political backing of the powerful unions, filed his own appeal last Friday.
The ruling found five laws violated the state constitutional right to quality education.
A lawsuit brought by students had argued that the last-hired, first-hired rules saddled schools, especially those in poor and minority neighborhoods, with bad teachers who effectively couldn't be fired.
The unions argue that the laws protect academic freedom.