In our new report, Opportunity at the Top: How America’s Best Teachers Could Close the Gaps, Raise the Bar, and Keep Our Nation Great, Emily Ayscue Hassel and I asked a simple question:  “Will our nation’s bold efforts to recruit more top teachers and remove the least effective teachers put a great teacher in every classroom?” We ran the numbers and discovered a disappointing answer: No. Even if these reforms were wildly successful, most classrooms still would not have great teachers.

Why does this matter? Only great teachers – those in the top quartile – achieve the student learning progress needed to close our nation’s achievement gaps and raise our bar to internationally competitive levels. Others do not.  Yet in two critical ways we fail to capitalize on the extraordinary resource of great teachers:

We lose too many of the best teachers: Contrary to popular belief, overall teacher turnover is modest compared with other professions. The crisis arises from our failure to keep the best teachers. Approximately 64,000 top-quartile teachers leave teaching every year, diminishing more than a million children’s learning prospects each following year.

We fail to leverage their talent for the benefit of students: The impact of great teachers who stay remains small over their careers. Only 600 students benefit from the instruction of an excellent elementary school teacher even if she stays on the job for 30 years. Our nation’s best teachers reach no more children than the very worst teachers.

If we don’t address these shortcomings, our glaring internal and international achievement gaps will persist, even if every state and district moves forward aggressively to recruit more great teachers and dismiss more ineffective ones.

If we do address them, by building a much more vibrant “opportunity culture” for America’s teachers, nearly 9 in 10 classes could be taught by great teachers in a mere half-decade.  The normal, expected experience of a student could be to have truly great teachers — the kind that today most children have only a few times in a whole school career.

Opportunity at the Top is the first in a series of reports supported by the Joyce Foundation, culminating in a set of recommendations for policymakers and educators about building an opportunity culture for America’s teachers.  Since we’re just getting started, we want to hear the best ideas about how to do that – so click the comment button!