The New York City Education Department released performance rankings of 18,000 public school teachers on Friday, the New York Times reported.
The rankings, which name teachers as well as their schools, rate teachers based on their students’ improvement on New York state math and English exams over five years, up until the 2009-10 school year, the Times reported.
The teacher rankings are an attempt by policy makers to distinguish between effective and ineffective teachers objectively, the Times reported.
"The Department of Education should be ashamed of itself," UFT President Michael Mulgrew said in a statement, according to Newsday. "It has combined bad tests, a flawed formula and incorrect data to mislead tens of thousands of parents about their children's teachers."
Critics point out that the rankings have many flaws, including the inability of high-ranking teachers to sustain their ratings by showing significant progress in students the next year. The data is also more than a year old and based on test scores that have been somewhat discredited, the Times reported.
Other skeptics argue that there are aspects the numbers cannot capture, including "supportive parents, a talented principal, the help of a tutor, allergies or a relentlessly barking dog outside the classroom," according to the New York Times.
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“I don’t want our teachers disparaged in any way based on this information,” the New York Schools' Chancellor Dennis Walcott, who released the information under a state appellate court order issued last week, told reporters during a briefing, Bloomberg reported. “It’s old data and it’s just one piece of information.”
New York is the second city in the US to publicize teachers' names and ratings, according to the Times. In 2010, The Los Angeles Times published its own set of ratings, in spite of fierce opposition from the local teachers’ union.
New York City argued that the public interest trumped concerns over the validity of the data. "The [reports], in accounting for many variables...provide parents with considerable information to make their own informed judgments," city lawyers wrote in March 2011, the Wall Street Journal reported. "This is precisely the sort of disclosure that FOIL was intended to ensure."
"Public education is paid for by the public, used by the public and of crucial public concern, so this data should be made public," said Robert Thomson, the Journal's managing editor.
Officials said 77 percent of the 18,000 teachers who received reports were still employed by the Education Department, according to the Times. However, many have moved on to administrative jobs or to teach subject areas or grade levels that were not included in the reports.
In a New York Times op-ed article this week, Bill Gates called the release of the New York City data a “big mistake.”
“Putting sophisticated personnel systems in place is going to take a serious commitment,” Gates wrote. “Those who believe we can do it on the cheap — by doing things like making individual teachers’ performance reports public — are underestimating the level of resources needed to spur real improvement.”