Do Teacher Rating Systems Work?

Last year, for the first time, every Michigan public school was required to measure teacher performance using four rating categories. The idea was that by expanding the range of ratings most districts use, teachers would get more individualized assessment and feedback on their strengths and weaknesses -- and appropriate professional development -- to help them improve, and in turn boost student learning.


It hasn’t worked out that way.

An Education Trust-Midwest survey of large Michigan school districts found that more than 99 percent of teachers were rated effective or highly effective on their 2011-2012 performance evaluations. Only 0.2 percent of teachers surveyed -- that's 2 in every 1000 teachers -- were rated ineffective.

The results of the Ed Trust-Midwest survey are even starker than the findings in an influential 2009 national study by The New Teacher Project called “The Widget Effect.” That study found that 94% of teachers were rated in one of the top two categories when more than two rating categories were used.

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