Here's Washington Post blogger Valerie Strauss, with her completely predictable take on the LA Times' decision to publish the teacher value-added data:

It's deja vu all over again with the Los Angeles Times and its value-added scores that supposedly tell us how effective are the teachers in the nation's second-largest school system.

The newspaper has printed its new ratings of elementary school teachers in the Los Angeles Unified School District based on how well students did on standardized tests. The idea is to use a formula that the newspaper had devised to assess the "value" a teacher added to a student's achievement.

The newspaper says its project takes into account the complexities of measuring teacher performance. But it essentially ignores some obvious points:

*Teachers aren't the only factor that go into how well a student does on a test;

*The tests aren't devised to evaluate teachers;

*There are lots of questions about how well the tests measure real student learning;

*Lots of experts say the whole value-added enterprise is not reliable and valid as a high-stakes fashion; and

*See this post by a prominent mathematician about why value-added is suspect for the purposes of evaluating teachers.

As I've said before, I'm glad that the LA Times is releasing this data, but I'm uncomfortable with it. I don't think this is a black-or-white issue. Contrary to Strauss's assertions, NOBODY thinks value-added systems are flawless (ditto for any test, even the best ones, like AP exams). But after pointing out that something isn't flawless, defenders of the status quo then conclude that it shouldn't be used at all, which is obviously nuts. This is, for example, their main line of attack against charter schools – and, come to think of it, pretty much any reform/innovation. Test scores and value-added systems shouldn't be the SOLE mechanism for evaluating teachers, but what about 40-60%??? NOBODY claims that all charter schools are great, but some are, so why shouldn't we do everything we can to facilitate the rapid expansion of the proven ones – and, more importantly, adopt the techniques that make them successful across ALL schools?!

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Posted at 12:48 PM ET, 05/09/2011