Controversial data-driven research behind the California court’s decision to reject teacher tenure

Underlying the California court’s decision on June 10, 2014 to reject teacher tenure as unconstitutional is a controversial body of academic research on teacher effectiveness.  The argument that won out was that tenure rules often force school districts to retain their worst teachers. Those ineffective teachers tend to end up at the least desirable schools that are packed with low-income and minority students. As a result, teacher tenure ends up harming low-income students who don’t have the same access as rich students to high-quality teaching.

But for this argument to carry weight we have to be able to distinguish good teachers from bad. How can we prove that California’s low-income schools are filled with teachers who are inferior to the teachers at high-income schools?

The nine plaintiffs, including Beatriz Vergara, who brought suit against the state. This slide, without names, was shown in court.

The nine plaintiffs, including Beatriz Vergara, who brought suit against the state. This slide, without names, was shown in court.

Dan Goldhaber, a labor economist at the University of Washington, and Eric Hanushek, a senior fellow at the Hoover Institution at Stanford, were two of the expert witnesses who spoke against teacher tenure in Vegara v. California. Both employ quantitative economic analysis in the field of education. They are both big proponents of using value-added measures to determine who is an effective teacher.

In value-added analysis, you  begin by creating a model that calculates how much kids’ test scores, on average, increase each year. (Test score year 2 minus test score year 1). Then you give a high score to teachers who have students who post test-score gains above the average. And you give a low score to teachers whose students show smaller test-score gains. There are lots of mathematical tweaks, but the general idea is to build a model that answers this question: are the students of this particular teacher learning more or less than you expect them to?  

This article also appeared here.

This article also appeared here.

Indeed, researchers using this value-added measure approach have sometimes found low-income schools have a high number of teachers who teach students with below-average test score gains.

Many researchers are questioning whether test-score gains are a good measure of teacher effectiveness. Part of the problem are the standardized tests themselves. In some cases, there are ceiling effects where bright students are already scoring near the top and can’t show huge gains year after year. In other cases, struggling students may be learning two years of math in one year, say catching up from a 2nd grade to a 4th grade math level. But the 5th grade test questions can’t capture the gains of kids who are behind. The test instead concludes that the kids have learned nothing. In both of these cases, with top and bottom students, the teachers would be labeled as ineffective.

Morgan Polikoff of the University of Southern California and Andrew Porter of the University of Pennsylvania looked at these value-added measures in six districts around the nation and found that there was weak to zero relationship between these new numbers and the content or quality of the teacher’s instruction. Their research was published in May 2014, after the Vegara trial ended. 



POSTED BY Jill Barshay ON June 11, 2014

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John Ryskamp

Note that the Judge continues the law which provides for equal “education.” That is in the process of being understood as equal learning. Which means that the whole debate is shifting to educational results. The old point of view is still the “opportunity to succeed” point of view, in which you learn if you succeed and you succeed if you learn. Means of evaluating both teacher and student performance are still caught up in these terms. Both terms point to what is learned, as the arena for debate. BUT that is an area in which the Court will not venture unless pushed by litigants. The reason is clear enough and is apparent from the New Jersey Abbott cases: where there is a right to equal learning, or, a right to learning, many more factors are subject to court order–for example, remediation in individual situations where the background of the student is in fact preventing learning. All this means, however, is that behind the right to education there are lurking other rights which the Court has not yet recognized. However, it will have to do so, because the right to equal education is becoming the right to learning.

The problem with this case, and with all other cases (except Abbott and a few others), is that it is a “walkaway” victory. By which I mean that the winners do not include, in their request for relief, court ORDERS changing the policy, changes which the winners can monitor. It means the Court retaining jurisdiction over the case. We are so rights deficient in this country that we still have a “get off my back” mentality, where, if one abuse is ended, that’s the end of the case. Instead, the history shows that the political system will bounce right back and attempt to subvert the right. Therefore, the political system must be continually monitored by the winners, and THAT means requesting equitable relief. This is certainly the lesson of Abbott, which is still under the jurisdiction of the Court after FORTY years.

Jill Barshay

@John Ryskamp. Thank you for your thought-provoking comments on whether the legal system is moving toward guaranteeing a “right to learn” in schools. Can you imagine a society where schools could be sued because some students haven’t shown sufficient learning or test-score gains?

As for court-monitoring afterwards, what would you propose for California? A monitoring of teachers’ VAMs across schools to ensure that low-income schools don’t continue to have lower-quality teachers than high-income schools?

I’ve always thought it would be an interesting thought experiment to do a great teacher swap. Move all the teachers at a low-income school into a high-income one. And take all the teachers at a high-income school and move them to a low-income one. It’d be fascinating to see what happens to their VAM scores.

Steve O'Donoghue

What is left out from this discussion is the undisputed fact that low income children in large urban districts (and many rural districts) don’t have experienced teachers because many experienced teachers leave those districts for higher paying , less stressful teaching positions in wealthy suburbs.

As has been documented, the low achieving students have tenured, unionized teaches. But so do the high achieving students.

And a regard does nothing to address how bad teachers get into the system: less than mediocre teacher certification programs and administrators who are buried by paperwork and don’t spend the time in the classroom necessary to adequately evaluate new teachers.

And Vergara does nothing to address the number one reason for low income students achieving lower: family income. The highest correlation between student achievement is family income, not teacher proficiency.

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