Looks like it's gonna be a full week without school for Chicago kids.

I've steered clear of saying much on the CTU strike because with so many people commenting and writing about this it gets hard to have anything original to say, but with so many people weighing in it's inevitable some of them will be saying ridiculous things that deserve calling out. One of the weirder memes I've seen going around the last few days is the notion that "the real problem here is that there's no evidence the teacher evaluations Rahm Emanuel wants to put in place work."

Let's think about this for a second. It's by and large true that there's no evidence that the evaluation system proposed in Chicago will improve student achievement. But that's because such evaluation systems have been implemented to date in only a few places, most of them for too little time to see any evidence of their effects. Until very recently, virtually all school districts in the country had very similar teacher evaluation systems that didn't take student learning (by any measure you like) into account or give teachers much real feedback about performance--and virtually all teachers were rated satisfactory or excellent. Those systems are still in place in most districts and, just for the record, there's not really any evidence that they improve student achievement either. To say that the Chicago Public Schools shouldn't try a new approach to teacher evaluation because there's no evidence it works is basically to say that we should never try anything new in public education--because things that have yet not yet been done by definition can't prove that they're effective.

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