The recent release of teachers’ value-added scores in
New York City (NYC) has kicked up a lot of dust. Regardless of the merits of publishing such
data for public consumption, we shouldn’t let the dust obscure the larger issue
that our previous attempts to improve teacher quality were so ineffectual. Policy involving teacher quality has historically
faced huge obstacles. Without direct
measurement of the effectiveness of teachers, we have been reduced to trying to
regulate teacher quality through proxies.
This reality is seen in NCLB, where we have called on states to declare
that schools are only staffed by “highly qualified teachers.” It is also seen in a variety of analyses that
try to compare either the distribution of teacher attributes such as experience
or degrees, or the distribution of teacher salaries across different
schools. But, the one thing that we have
learned from research is that neither of these approaches makes any sense,
because the things that are being measured are unrelated to actual
effectiveness in the classroom.
The NYC
score release brings two related and relevant issues squarely to mind. First, we now have the capacity to assess the
impact of teacher performance on students in a very general way. We can do this in a majority of states and
cities in the nation, and could do it in all if there was sufficient political
will. Second, the release begins to give
us some appreciation for whether or not we are systematically biasing education
away from the neediest students. Since
before Brown vs. Board of Education,
there has been concern that political forces align to deprive minorities and
poor students of an equal opportunity to a high quality education. Until
now, however, it was difficult to look clearly at this issue.
We are
approaching a time when we can develop objective measures of the distribution
of actual teacher effectiveness. The
measures can include value-added information like that in NYC. It can also include rigorous evaluation
information like that developed in Washington, DC.
The potential power of this type of
analysis is seen vividly in the Ed Trust West report on teacher effectiveness across Los Angeles
schools. While it is admittedly still
not easy to distinguish between differences in teacher effectiveness across
schools and differences in the students who select particular schools, we can
and should at least begin to map out the true distribution of teaching talent
across all our schools. Doing this, and
paying attention to it, is vitally important for fulfilling our promises of
equal opportunities for all students.
Doing it is also important for guiding our various policy efforts
designed to ensure that our disadvantaged students get an equal shake.
Continuing
anachronistic regulatory and policy efforts aimed at input measures and
credentials does not make sense when the alternative — a capacity to look at
the varying levels of education that are actually being provided to our
students — is available to us.
Eric A. Hanushek