David Wiley has a great post up on efficacy and OER in response to my original post about Pearson’s efficacy plan. He opens the piece by writing about Benjamin Bloom’s famous “2 sigma” problem:
The problem isn’t that we don’t know how to drastically increasing learning. The two-part problem is that we don’t know how to drastically increase learning while holding cost constant. Many people have sought to create and publish “grand challenges” in education, but to my mind none will ever be more elegant than Bloom’s from 30 years ago:
“If the research on the 2 sigma problem yields practical methods – which the average teacher or school faculty can learn in a brief period of time and use with little more cost or time than conventional instruction – it would be an educational contribution of the greatest magnitude.” (p. 6; emphasis in original)
So the conversation can’t focus on efficacy only – if there were no other constraints, we actually know how to do “effective.” But there are other constraints to consider, and to limit our discussions to efficacy is to remain in the ethereal imaginary realm where cost doesn’t matter. And cost matters greatly.
David then launches into a discussion of what he calls his “golden ratio,” or standard deviations per dollar. I have long been a fan of this formulation and quote it frequently. I’m not going to try to summarize his explication of it in his post; you really should go read it. But I would like to tease out a few implications here.