Dominic J. Brewer

Does Teacher Certification Matter? High School Teacher Certification Status and Student Achievement

We empirically test how 12th-grade students of teachers with probationary certification, emergency certification, private school certification, or no certification in their subject area compare relative to students of teachers who have standard certification in their subject area. We also determine whether specific state-by-state differences in teacher licensure requirements systematically affect student achievement. In mathematics, we find teachers who have a standard certification have a statistically significant positive impact on student test scores relative to teachers who either hold private school certification or are not certified in their subject area. Contrary to conventional wisdom, mathematics and science students who have teachers with emergency credentials do no worse than students whose teachers have standard teaching credentials.

Why Don't Schools and Teachers Seem to Matter? Assessing the Impact of Unobservables on Educational Productivity.

Using data drawn from the National Educational Longitudinal Study of 1988, which allows students to be linked to particular teachers and classes, we estimate the impact of observable and unobservable schooling characteristics on student outcomes. A variety of models show some schooling resources (in particular, teacher qualifications) to be significant in influencing tenth-grade mathematics test scores. Unobservable school, teacher, and class characteristics are important in explaining student achievement but do not appear to be correlated with observable variables in our sample. Thus, our results suggest that the omission of unobservables does not cause biased estimates in standard educational production functions.

Class Size and Student Achievement

Schooling has multiple purposes. In the long run, higher levels of schooling are associated with higher earnings and economic mobility, better health, lower mortality rates, and greater democratic participation. For these reasons, most societies require children to attend school for a specified number of years or until they reach a certain age. Many of the benefits of schooling occur in part because students learn some new knowledge or skills that enhance their ability to communicate, solve problems, and make decisions. Much of the debate over schooling is essentially about how to maximize the amount of student learning, typically as measured by various assessment instruments such as standardized achievement tests. From a societal viewpoint, since resources—most notably, time—are required for learning, and are scarce, the amount of learning needs to be maximized at least cost. Learning is complex, involving cognitive processes that are not completely understood. Typically, school systems have established a primary mode of learning that involves groups of students of about the same age interacting with a single individual leading activities in a confined physical space, directed toward learning a particular topic—in other words, students are placed in classes. The number of other students in the class can vary. At the extreme, there can be one or more adults facilitating learning—teachers—with one or two students. At the other, a student may be one of a few hundred being taught by a single instructor (or, with new Internet technology, one of millions). The number of students in a class has the potential to affect how much is learned in a number of different ways. For example, it could affect how students interact with each other—the level of social engagement. This may result, for example, in more or less noise and disruptive behavior, which in turn affect the kinds of activities the teacher is able to promote. It could affect how much time the teacher is able to focus on individual students and their specific needs rather than on the group as a whole. Since it is easier to focus on one individual in a smaller group, the smaller the class size, the more likely individual attention can be given, in theory at least. The class size could also affect the teacher’s allocation of time and, hence, effectiveness, in other ways, too—for example, how much material can be covered. Teachers may choose different methods of teaching and assessment when they have smaller classes. For example, they may assign more writing, or provide more feedback on students’ written work, or use open-ended assessments, or encourage more discussions, all activities that may be more feasible with a smaller number of students. Exposure to a particular learning environment may affect learning over the time period of exposure, or it may have longer term or delayed effects (e.g., by increasing self-esteem or cognitive developments that have lasting effects). For these reasons, changes to the class size are considered a potential means of changing how much students learn. Not only is class size potentially one of the key variables in the “production” of learning or knowledge, it is one of the simplest variables for policymakers to manipulate. However, the amount of student learning is dependent on many different factors. Some are related to the classroom and school environment in which the class takes place, but others are related to the student’s own background and motivation and broader community influences. When we ask whether class size matters for achievement, it is essential to ask also, how class size matters. This is important for three reasons. First, if we can observe not only achievement differences, but also the mechanisms through which the differences are produced, this will increase our confidence that the differences are real, and not an artifact of some unmeasured or inadequately controlled condition. Second, the effects of class size may vary in different circumstances, and identifying how class size affects achievement will help us to understand why the effects of class size are variable. Third, the potential benefits of class-size reduction may be greater than what we observe. For example, suppose class-size reductions aid achievement, but only when teachers modify instructional practices to take advantage of the smaller classes. If a few teachers make such modifications, but most do not, then understanding how class size affects achievement in some cases will help reveal its potential effects, even if the potential is generally unrealized.

Detracking America's schools: Equity at zero cost?

Schools across the country are ending the practice of grouping students based on ability, in part, because of research indicating that tracking hurts low-ability students without helping students of other ability levels. Using a nationally representative survey conducted by the National Center for Education Statistics, (NCES) we reexamine the impact of tracking on high school student achievement through the estimation of a standard education production function. This approach allows us to control for the possibility that track is correlated with factors such as class size and teacher education. In addition, we address the possibility that there are unobserved student or school characteristics that affect both achievement and track placement. Our results indicate that abolishing tracking in Americas schools would have a large positive impact on achievement for students currently in the lower tracks, but that this increase in achievement would come at the expense of students in upper-track classes.

Career Paths and Quit Decisions: Evidence from Teaching

Conventional models predict that workers consider employment opportunities and monetary rewards expected over their lifetimes when making current period decisions such as whether to quit a job. This article tests the hypothesis that later career opportunities affect quit decisions by examining the relationship between teaching and school administration. Evidence on the extent to which administrative positions are available to teachers, and the salary premia associated with them, is presented. Discrete time logit-hazard models of teacher quits, estimated using data from New York State, provide some support for the hypothesis, though the magnitudes of the estimated effects are small.

Does it pay to attend an elite private college? Evidence on the effects of undergraduate college quality on graduate school attendance

Much attention has recently focused on the rapidly rising costs of a college education, and whether the benefits of attending an elite private college have kept pace with the increasing costs. In this paper we analyze whether undergraduate college quality affects the likelihood that an individual attends graduate school. Using data on three cohorts of students from the National Longitudinal Study of the High School Class of 1972and High School and Beyond , we find that on balance attendance at an elite private college significantly increases the probability of attending graduate school, and more specifically, graduate school at a major research institution. ( JEL I21, J24)

A Three-way Error Components Analysis of Educational Productivity

Previous research on educational productivity has decomposed the variance in student test scores into school and class effects.In this paper, we extend this work to include differences attributable to teachers as well as to schools and classes. Using data drawn from the National Educational Longitudinal Study of 1988, we find that unobservable School, teacher, classroom characteristics are important factors in explaining 10th-grade mathematics achievement, and account for the majority of the variation that is explained by educational variables.

Estimating the Cost of National Class Size Reductions Under Different Policy Alternatives

We estimate the operational costs of nationwide class size reduction (CSR) programs under various policy alternatives, including the specified class size, flexibility in implementation, and whether the policy is targeted toward at-risk students. Depending on the specific options chosen, the estimated costs vary from about

Tracking in the United States: Descriptive statistics from NELS

2 billion per year to over

How should we measure the effect of ability grouping on student performance

11 billion per year. These estimates could be further increased by teacher salary hikes necessitated by the rapid increase in the demand for teachers that results from CSR. Policymakers considering such a policy on a large scale should question whether it is the most cost-effective way of boosting student achievement.