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MSPnet Blog: “Sisyphus visits Teacher Impact Mountain”

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posted November 12, 2014 – by Brian Drayton

I guess one of the underlying themes of this blog is the search for perspective amidst the ever-whirling winds of ed reform rhetoric. With regard to ed reform policy as it’s usually construed, the latest election won’t make a lot of difference — both parties’ reform hawks are into accountability for teachers and students (but not school boards, legislators, governors…), privatization, charter schools, more high tech, etc.
But if you lift your weary head over the mounds of think tank documents to just to one side or the other of the usual frames, lo and behold! there’s a whole society out there, and it turns out that the social matrix has a lot of impact on what happens inside the school walls.
With this flourish, I present this week’s interesting read, from P.L Thomas’s blog The Becoming Radical. His latest post is entitled “Unpacking education and teacher impact.”  Deploying more statistics than you might expect from a literature professor, he explores the evidence about how much teacher impact upon student outcome measures it is realistic to expect.  In so doing, he does not claim that teachers have no impact on such measures;  and he also points out that teachers can have a lot of impact in other ways, which might be more important, on the whole.  (He also places this question of teacher impact alongside other questions for which the evidence is pretty strong, such as the ill effects of grade retention, and of corporal punishment, and provides excellent examples of  How to Clarify the Terms of A Debate.)

The bottom line is that research has repeatedly established that school effects explain between 14% and 20% of student achievement;  things outside of school account for about 60% (the other 20% is noise).  Of the (let’s call it) 15% weight that can be attributed to school factors, perhaps ±50% (so something like 7-10%, ±) can be attributed to teachers.   On this basis of this and other evidence, Thomas concludes “making claims about education being the single or sole factor in success or that the teacher is the single most important factor in achievement is misleading, overly simplistic.”

But he goes further, because what is all this pressure for educational attainment about?  Mostly the arguments are for gains in students’  financial welfare/social mobility (and other data he adduces show how little of that our society currently has).  But if you’re interested in increasing equity, the data show that “within social class and race, educational attainment has significant influence, but…education alone appears less effective in overcoming large social inequities such as classism and racism.”

My dad always used to say, “Welp, if you want a better society, you’re going to have to get better people.”  But if we’re really about evidence-based policies, we have to admit that if we want freer people we are going to have to get a better society.  Schools are a part of the picture — but we’ve got to keep looking at the whole landscape.


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