Stop saying "best practice"...

...there's no such thing, unless you qualify the claim with the relevant conditions or parameters.

"This is best practice under these conditions...."  Or, "This is best practice for these students...."

It's logically and practically impossible to imagine there's a best practice for every student, given the wide range of ability levels, learning styles, brain development, and more present among any group of 30 students--even 30 in the same grade.

There may be something like a best practice for maximizing aggregate outcomes on some particular measure. In other words, there may be a practice that generates the greatest likelihood of raising something like a standardized test score for the greatest portion of those 30 kids in the class room.  It won't necessarily raise everyone's score, or, even more likely, all 30 individual's score as much as another approach/practice may have raised a particular 1 or 2 or 3 students' scores.

What I'm getting at is another of the assumptions embedded in the standardization process, and especially the testing that accompanies it.  The push toward standardization, measurement and assessment focuses our attention on aggregate outcomes.  We assume that those things the tests measure are all and only what we think is worth a student knowing, understanding or doing.  Further, we assume that collectively aggregating all student scores into a few measures, the improvement of which is the primary objective, is worthwhile.

For example, if I could get 27 students' test scores to go up the greatest possible amount (as if we could know that), but the 3 other students' scores stayed flat, or even dropped, I'd be a hero--90% went up.  But was there some other "practice" (not best for the aggregate, but best for those 3 students) that would have raised those 3 scores?  If raising their scores would have meant trading off a different 3 students' scores, what would be the best practice?  What about trading off 5 other students' scores?

So, we need to talk about "best practice" while acknowledging that we make guesses at tradeoffs among students, while maintaining the objective of maximizing as many of the 30 students' scores as possible.

It may not sound like it, but what I've just raised is a complicated set of trade offs and balances in pursuit of one particular goal--aggregate outcomes.  You can't spend much time in a class room without realizing that some students respond very differently to a teaching practice, "best" or otherwise.  When I think about what we do in my 8th grade English room, I try to create a variety of tasks, activities, assignments, etc., knowing that some of that work will appeal to one part of the class, and another portion of the work will appeal to some other students.  I've found very few things that stimulate, engage, inspire, whatever, ALL the students in the room.  And some students are engaged by very little of what we do.  Striking this balance is the constant endeavor of identifying so-called "best practice" in the first place.

Ultimately, "best" is something of a trope.  We won't really get there, in part because we disagree about what we should be pursuing in the first place.  That complicates the question before we even begin to answer it.