Earlier quoted context omitted.
> The overall environment matters more than the teacher. You seem to be suggesting that the quality of the teacher can play only a minor role in the educational outcome for disadvantaged students. Yet there is considerable evidence to support the opposite view. Here is a summary of a few studies as reported in Teaching as Leadership [1]: "The schools that are highly effective produce results that almost entirely over…
I work at a public high school. Marzano is currently overseeing the building I work in as our educational "partner". He hasn't set foot in a classroom since the 70s and is utterly clueless. The article makes some good points and mirrors the experience of many ambitious teachers I've seen ground out of "the system".
That's why there are people who study the behavior of teachers in the aggregate (and, yes, this involves measuring outcomes through testing), and the associated educational outcomes, so that policymakers at various levels can guide the educational system as a whole in a way that will be the most helpful for the most students. This is, broadly speaking, just one example of how social science research and policymaking is done.
Of course, none of this means that Marzano is not clueless. He might be clueless for entirely separate reasons.