EDUCATIONAL OUTCOMES IN OECD COUNTRIES
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following factors has a consistent impact on achievement: the level of teacher education,
the pupil-teacher ratio, the characteristics of administration, or the facilities of the
school. Specifically, aggregating results across studies, a minority of estimates are
statistically different from zero (at the 5 percent level or better), and the studies do not
even uniformly indicate improvements in performance with increased resources. A
second line of studies focuses on financial inputs. A number of studies simply relate
spending per student to achievement or capture teacher differences by teacher salaries.
While these studies tend to be lower quality, they also fail to show a consistent
relationship between financial resources and achievement.
These results have been controversial. A variety of debates have taken place around
the correct interpretation of prior work (see, for example, Burtless (1996)). The most
important line of debate has involved study quality and whether or not these works
adequately control for various inputs that might complicate the interpretation of
resources. For example, the statistical models may not adequately account for other
inputs that affect achievement such as the quality of family inputs. The estimates might
then erroneously attribute the higher achievement due to better family factors to some of
the characteristics of schools.
A simplistic view of this argument - convenient as a straw man in public debates - is
that ‘money never matters.’27 The research of course does not say that. Nor does it say
that ‘money cannot matter.’ It simply underscores the fact that there has historically
been a set of decisions and incentives in schools that have blunted any impacts of added
funds, leading to inconsistent outcomes. That is, more spending on schools has not led
reliably to substantially better results.
6.2. Teacher quality
The most current research on school inputs and achievement has also led to another set
of conclusions - that teacher quality is enormously important in determining student
achievement. This work has concentrated on whether some teachers consistently
produce more gains in student achievement than other teachers.28 Working with
extensive panel data on individual students from different U.S. states, these studies have
confirmed large differences among teachers in terms of outcomes in the classroom.
But, they have also shown that the observed differences are not closely related to
commonly observed characteristics of teachers (such as amount of teacher education).
Some attributes of teachers - such as having one or two years of experience - have
explained part of the differences in teacher quality, but these factors are a small part of
the overall variance in teacher results.29 This inability to identify specific teacher
27 For the historical framing of the question, see the exchange between Greenwald, Hedges, and Laine (1996) and Hanushek
(1996).
28 See, for example, Hanushek (1971, 1992), Rockoff (2004), Rivkin, Hanushek, and Kain (2005), and a number of subsequent
studies reviewed in Hanushek and Rivkin (2010).
29 There is some indication that teachers’ own academic skills measured by scores on achievement tests may be an important
factor (see Wayne and Youngs (2003), Eide, Goldhaber, and Brewer (2004), and Hanushek and Rivkin (2006) for reviews), but
methodologically more sophisticated work is needed before conclusive assessments can be given on this dimension.