Abstract

Abstract This paper examines the effect of early childhood investments on college enrollment and degree completion. We use the random assignment in the Project STAR experiment to estimate the effect of smaller classes in primary school on college entry, college choice, and degree completion. We improve on existing work in this area with unusually detailed data on college enrollment spells and the previously unexplored outcome of college degree completion. We find that assignment to a small class increases the probability of attending college by 2.7 percentage points, with effects more than twice as large among blacks. Among students enrolled in the poorest third of schools, the effect is 7.3 percentage points. Smaller classes increase the likelihood of earning a college degree by 1.6 percentage points and shift students towards high-earning fields such as STEM (science, technology, engineering and mathematics), business and economics. We find that test score effects at the time of the experiment are an excellent predictor of long-term improvements in postsecondary outcomes. Education is intended to pay off over a lifetime. Economists conceive of education as a form of "human capital," requiring costly investments in the present but promising a stream of returns in the future. Looking backward at a number of education interventions (e.g., Head Start, compulsory schooling), researchers have identified causal links between these policies and long-term outcomes such as adult educational attainment, employment, earnings, health and civic engagement They therefore rely upon short-term outcomes -primarily standardized test scores -as their yardstick of success. A critical question is the extent to which short-term improvements in test scores translate into long-term improvements in well-being. Puzzling results from several evaluations make this a salient question. Three small-scale, intensive preschool experiments produced large effects on contemporaneous test scores that quickly faded We examine the effect of smaller classes on educational attainment in adulthood, including college attendance, degree completion and field of study. We exploit random variation in class size in the early grades of elementary school created by the Tennessee Student/Teacher Achievement Ratio (STAR) Experiment. Participants in the STAR experiment are now in their thirties, an age at which it is plausible to measure 1 completed education. Our postsecondary outcome data is obtained from the National Student Clearinghouse (NSC), a national database that covers approximately 90 percent of students enrolled in colleges in the U.S. We find that being assigned to a small class increases the rate of postsecondary attendance by 2.7 percentage points. The effects are considerably higher among populations with traditionally low rates of postsecondary attainment. For Black students and students eligible for free lunch the effects are 5.8 and 4.4 percentage points, respectively. At elementary schools with the greatest concentration of poverty, measured using the fraction of students receiving a subsidized lunch, smaller classes increase the rate of postsecondary attendance by 7.3 percentage points. We further find that being assigned to a small class increases the probability of earning a college degree by 1.6 percentage points. Smaller classes shift students toward earning degrees in high-earning fields such as science, technology, engineering and mathematics (STEM), business and economics. Our results shed light on the relationship between the short-and long-term effects of educational interventions. The short-term effect of small classes on test scores, it turns out, is an excellent predictor of its long-term effect on adult outcomes. We show this by adding K-3 test scores to our identifying equation; the coefficient on the class size dummy drops to zero. The coefficient on the interaction of class size and test scores is also zero, indicating that the scores of children in small classes are no less (or more) predictive of adult educational attainment than those of children in the regular classes. Our analysis identifies the effect of manipulating a single policy-relevant educational input on adult educational attainment. By contrast, the early-childhood interventions for which researchers have identified lifetime effects (e.g., Head Start, Abecederian) are multi-pronged, including home visits, parental coaching and vaccinations in addition to time in a preschool classroom. We cannot distinguish which dimensions of these treatments generate short-term effects on test scores, and whether they differ from the dimensions that generate long-term effects on adult well-being. The effective dimensions of the treatment are also ambiguous in the recent literature on 2 classroom and teacher effects. For example, THE TENNESSEE STAR EXPERIMENT The Tennessee Student/Teacher Achievement Ratio (STAR) Experiment randomly assigned class sizes to children in kindergarten through third grade. The experiment was initiated in the 1985-86 school year, when participants were in kindergarten. A total of 79 schools in 42 school districts participated, with over-sampling of urban schools. An eventual 11,571 students were involved in the experiment. The sample is 60 percent white and the balance African American. About 60 percent of students were eligible for subsidized lunch during the experiment. The experiment is described in greater detail elsewhere (Word, et al