By Ben Velderman

SEATTLE – Researchers with the Bill and Melinda Gates Foundation say they have finally cracked the code to meaningful teacher evaluations, which will enable school leaders to “identify groups of teachers who are more effective in helping students learn.”

It’s a day many teacher union leaders thought – and hoped – would never come, as the findings thoroughly contradict union doctrine that says all teachers should be treated as equals.

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On Tuesday, the Gates Foundation announced that not only can teacher evaluations be used to sort effective teachers from ineffective ones, but it affirmed that student test scores should play an important role in making those determinations.

Those conclusions are the result of the foundation’s three-year, $45 million Measures of Effective Teaching (MET) Project.

According to the foundation’s report, student test scores are one of three measurements that should be used to determine how well a teacher is performing in the classroom. Researchers say multiple classroom observations (involving multiple observers) and student surveys should also play a part.

Researchers demonstrated that this combined approach works by conducting a nationwide experiment involving thousands of educators.

Lyndsey Layton of the Washington Post writes:

“Researchers videotaped 3,000 participating teachers and experts analyzed their classroom performance. They also ranked the teachers using a statistical model known as value-added modeling, which calculates how much an educator has helped students learn based on their academic performance over time. And finally, the researchers surveyed the students, who turned out to be reliable judges of their teacher’s abilities. …

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“They used all that data to identify teachers who seemed effective. And then they randomly assigned students to those teachers for an academic year.

“The teachers who seemed to be effective were, in fact, able to repeat those successes with different students in different years, the researchers found. Their students not only scored well on standardized exams but also were able to handle more complicated tests of their conceptual math knowledge and reading and writing abilities.”

This is huge news.

For years, teacher unions have resisted efforts to make student learning (as measured by student test scores) part of teacher evaluations. The Obama Administration has used its Race to the Top education initiative to prod states into creating tougher and more meaningful evaluations, often ones that make use of student test scores.

Some union leaders – such as American Federation of Teacher s President Rhonda “Randi” Weingarten – have grudgingly accepted the limited use of test scores in rating teachers. But that only came after years of pushing and prodding by education reformers.

National Education Association leaders, on the other hand, resisted the entire idea until their 2011 convention. Even after delegates voted to reverse their long-standing opposition and join the 21st century, NEA leaders threw cold water on the idea by saying that every standardized test in existence is flawed and their results are too unreliable to be used in teacher evaluations.

Not only does the Gates Foundation report affirm that test scores can play a part in rating teachers, it offers scientific proof that some teachers are simply better at their jobs than others.

School leaders now know how they should be evaluating their teaching staffs, and policymakers now have motivation to reexamine a number of K-12 policies, including seniority-based layoffs, merit pay, and teacher tenure.