I am pretty sure I know what you are referring to. And I'll cite the works of Jeannie Oakes. I don't recall the name of the study she had done, it's been a few years since I've read it, but it goes something like this:
In areas where the majority of the students are of lower SES, the schools tend to use lesson plans that have the qualities of what was referred to as classical conditioning (as in Pavlov and Skinner). These schools tend to have larger classrooms and they also to use the "one size fits all" lesson plans, to follow the lesson plans provided by the instructional guide that comes with the Teachers edition.
In areas where the majority of the students are of higher SES, the schools tend to use lesson plans that have the qualities of what was referred to as higher order and abstract thinking (as in Piaget). These schools tend to have smaller classrooms, better equipment, etc, and the lesson plans tend to allow the student to reach the correct conclusion on their own, as opposed to a mechanical way of thinking (as in the former example).
What is the difference? Lower SES schools produce the type of worker that would be optimal to follow orders and to follow instructions, in short blue collar jobs. Higher SES schools would produce white collar workers. Jeannie Oakes' study confirmed that this is the norm, but it's not the only factor however, there are several other variables to keep in mind as well.
