An agreement between the Los Angeles Unified School District and the Los Angeles teachers' union has been reached that would for the first time include student test scores in teacher evaluations, the L.A. Times reports.

The new system is to be implemented for the coming school year, contingent upon a further agreement between the district and United Teachers Los Angeles on how, specifically, the student test scores will factor into evaluations.

The agreement comes one month after Los Angeles County Superior Court Judge James C. Chalfant ruled in favor of a group of unidentified parents that claimed the district had violated the Stull Act, a 41-year-old state law that mandates student achievement measures -- like test scores -- be used in gauging teacher performance. The parents’ attorneys successfully argued that L.A. Unified’s lack of an evaluation system that effectively identities teacher weaknesses deprives students of their constitutional right to educational equality.

On Tuesday, attorneys for the district and the unions representing teachers and administrations decided on a Dec. 4 deadline to implement a system for including student test scores in performance reviews. On Sept. 4, all parties will return to court with a progress update to ensure the district is on pace to meet the deadline.

The Contra Costa Times reports that UTLA attorney Jesus Quinonez said the union and district will meet this week to work out details regarding the evaluation system.

According to the Times, about 700 teachers and principals representing 100 schools are currently participating in a voluntary evaluation program that takes into account “academic growth over time,” a measure based on student test scores.

UTLA has opposed the voluntary program -- spearheaded by district superintendent John Deasy -- claiming that test scores are too unreliable to incorporate in decisions regarding firing, tenure and merit pay.

In 2010, a report by the Los Angeles Times published the names of more than 6,000 teachers tied to their value-added ratings. But researchers at the University of Colorado found that more than a third of Los Angeles Unified teachers would have had different scores if a slightly different formula had been used to calculate those ratings.

A similar situation occurred in New York in February, when a lengthy battle waged by the local teachers' union ended in the release of more than 12,000 individual New York City teacher ratings, amid great controversy. In question: the ratings' use of value-added analysis, which calculates teacher effectiveness in improving student performance on standardized tests -- based on past test scores. The forecast figure is compared to the student's actual scores, and the difference is considered the "value added," or subtracted, by the teachers. UTLA had previously proposed a similar evaluation system for its teachers.

In both New York and LA, some saw the release as a step forward in using student data and improving transparency and accountability by giving parents access to information on teacher effectiveness. The court ruling that granted public access to the ratings states, "the reports concern information of a type that is of compelling interest to the public, namely, the proficiency of public employees in the performance of their job duties."

But to others, the move was misguided, and signaled an over-reliance on incomplete or inaccurate data that publicly shames or praises educators, whether deserving or not. Value-added models generally don't control for demographic factors like poverty, race, or English-learner or special education status, which some say are crucial to evaluating teachers. Some believe that ratings will undermine overall education reform by negatively affecting teacher morale and teacher recruitment, as well as by reinforcing the false notion that testing is everything. New York's ratings, which were developed as a means for internal assessment, were also based on small amounts of data and have large margins of error.

Under a new Ohio law, public school districts will be required to give each teacher a grade by the 2013-14 academic year. Half of each educator’s score will be based on how much students learn, as determined by their test scores. Decisions regarding salary, promotions and firings will then be based on these results.

In Florida, it will be mandatory by 2014 to use student scores on standardized exams to help evaluate teachers and set their pay under a new state law.

Meanwhile, protests by parents, teachers and administrators have been organized nationwide in response to a perceived overreliance on test scores in gauging student achievement and evaluating teachers.

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