Right. Let's not overlook the fact that T can influence both B and P. The equation is nonlinear, and IMO dominated by cross-terms. Teachers and teaching meth

Right. Let's not overlook the fact that T can influence both B and P. The equation is nonlinear, and IMO dominated by cross-terms. Teachers and teaching methods that are engaging, for example, will tend to promote better behavior within the classroom. Teachers and methods that inspire most of the class to think learning is "cool" and worthwhile will improve the whole peer group. There is a lot of feedback involved. Unfortunately, as you point out, the expected "role of a teacher" isn't really well geared to produce excellent teachers using excellent methods.