Settling the "3 great teachers in a row" debate 1. Economists Eric Hanushek and others make a claim. 2. Diane Ravitch offers a rebuttal. 3. I weigh in. * * *
The Washington Post excerpts a chunk of Diane Ravitch's book recently.
Ravitch lays out the "3 great teachers in a row" claim advanced by 2 different groups of economists, plus a statistician.
She then argues that they're wrong.
I think there's some room for both sides, if we get precise.
Economists Hanushek and Rivkin projected that “having five years of good teachers in a row” (that is, teachers at the 85th percentile) “could overcome the average seventh-grade mathematics achievement gap between lower-income kids (those on the free or reduced-price lunch program) and those from higher-income families."
She then cites some similar stuff from statistician William Sanders (3 years in a row) and Tom Kane and Doug Staiger (4 years in a row).
Her response is:
This is akin to saying that baseball teams should consist only of players who hit over .300 and pitchers who win at least twenty games every season; after all, such players exist, so why should not such teams exit.
The fact that no such team exists should give pause to those who believe that almost every teacher in almost every school in almost every district might be a superstar if only school leaders could fire at will.
I'm not sure the economists are saying precisely what Ravitch contends they are saying.
a. There's an assertion -- 3 or 4 or 5 good teachers in a row COULD to closing the Achievement Gap. No question they've said that.
b. There's a variation of that assertion -- 3 or 4 or 5 good teachers in a row DOES close the Achievement Gap. I'm not sure if they've said that or not. I don't think they have.
That is, you could actually try to dig up kids who have lucked into this statistical anomaly.* And see what happened to their test scores.
c. And then there's the implications of that assertion. Ravitch's view, if I understand correctly, is: so what?
You can't plausibly posit a world where 3 million of the current 3.5 million schoolteachers stop teaching, leaving just the best half million in classrooms. So if we assume teaching skill as relatively fixed, we should stop trying to talk about kids receiving a teacher all-star team.
4. Me Continued
Ravitch's analogy is correct for pro baseball. But there are indeed teams where all of the players hit .300.
That's college baseball.
In college baseball, the top 50 teams all average well over .300. The best -- like University of Pittsburgh in 2010 -- had every starter well over .300. The low was .322.
It's easier to hit well in college.
First, they use aluminum bats, not wood. There are other factors. Let's stick with that one.
So what I think we can all agree on is: we want to make it easier for teachers to be .300 hitters.
The question becomes -- what is the "aluminum bat" that would allow many more teachers to "hit .300"?
Ravitch might say the aluminum bat is: better curriculum.
Kane might say the aluminum bat is: some group of teacher behaviors, which seem correlated to high achievement.
Hanushek might say the aluminum bat is: cutting the .200 hitters. (Then kids would arrive to each teacher's classroom with better skills, making it easier to have .300-like performance without changing anything in most teachers).
I wonder if high-leverage, high-dosage coaching may be the aluminum bat.
Quick story. Two weekends ago we had 2 coaches at the TFA summit. So Orin was one sub, and I was the other. (I live-blogged my observations). The 4 teachers rated my feedback as 8 out of 10. I slightly underperformed our average, which was 8.6 that weekend.
The 4 teachers Orin coached rated his feedback 10, 10, 10, 10. Let me get my calculator -- yep, that's an average score of 10.
If coaching is indeed a potential aluminum bat, we'd have to find a way to make sub-par coaches (like me) into .300 coaches (like Orin).
* * *
*What are the odds of getting 4 top quintile teachers in a row? Ie, if this were perfectly random (which it's almost assuredly not), the odds of a Kane scenario would be 0.2 to the 4th power right? That's 16 kids out of every 10,000.