(Guest Post by Matthew Ladner)
So today we get yet another random-assignment study showing that a choice program produced significant student gains for those lucky enough to get into it. This time it is Harlem Success Academy– a mere 13 to 19 percent test score improvement associated with winning the lottery to attend there.
What’s that you say? Yes, true, that is far larger than the average test score differences between Massachusetts and Mississippi on NAEP, so yes, I am excited. Or I’m trying to be.
It’s just that we’ve crushed a piece of coal with our gauntleted hand to produce a diamond so many times now, that it has lost something of its charm. The other side will trot out their non-random assignment studies and reporters will mistakenly continue to use the adjective “mixed” to describe the research.
Sigh
I’m still waiting for any random assignment evidence that these programs do any harm by the way.
Posted by matthewladner 
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