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Tim R. Sass

Assessing the Benefits of Education in Early Childhood: Evidence from a Pre-K Lottery in Georgia

Numerous studies have demonstrated a strong link between participation in pre-K programs and both short-term student achievement and positive later-life outcomes.  Existing evidence primarily stems from experimental studies of small-scale, high-quality programs conducted in the 1960s and 1970s and analyses of the federal Head Start program.  Meanwhile, evidence on state-funded pre-K programs, with no income restrictions, is scant and inconclusive.  Using enrollment lotteries for over-subscribed school-based sites in Georgia’s universal pre-K program, we analyze the impact of participation on elementary school outcomes.  Lottery winners enter kindergarten more prepared in both math and reading than non-winning peers. Gains fade by the end of kindergarten, and some negative achievement effects emerge by grade 4. Free-and-reduced-price meal (FRPM) students benefit more compared to non-FRPM students in later grades, suggesting greater benefits from attendance for disadvantaged students.  Although we find no effects for discipline, lottery winners had one fewer absence each grade after kindergarten.

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Learning-Mode Choice, Student Engagement, and Achievement Growth During the COVID-19 Pandemic

The COVID-19 pandemic initially resulted in an unanticipated and near-universal shift from in-person to virtual instruction in spring 2020. During the 2020-21 school year, schools began to re-open and families were faced with decisions regarding the instructional mode for their children. We leverage administrative, survey, and virtual-learning data to examine the determinants of family learning-mode choice and the effects of virtual education on student engagement and academic achievement. Family preference for virtual (versus face-to-face) instruction was most highly associated with school-level infection rates and appeared relatively uniform within schools. We find that students who were assigned a higher proportion of instructional days in virtual mode experienced higher rates of attendance, but also negative student achievement growth compared to students who were assigned a higher proportion of instructional days in face-to-face mode. Students belonging to marginalized groups experienced more positive associations with attendance but were also more likely to experience lower student achievement growth when assigned a greater proportion of instructional days in virtual mode. Insights from this study can be used to better understand family preference as well as to target and refine virtual learning in a post-COVID-19 society.

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Testing, Teacher Turnover and the Distribution of Teachers Across Grades and Schools

Teacher turnover has adverse consequences for student achievement and imposes large financial costs for schools. Some have argued that high-stakes testing may lower teachers’ satisfaction with their jobs and could be a major contributor to teacher attrition. In this paper, we exploit changes in the tested grades and subjects in Georgia to study the effects of eliminating high-stakes testing on teacher turnover and the distribution of teachers across grades and schools. To measure the effect of testing pressures on teacher mobility choices we use a "difference-in-differences" approach, comparing changes in mobility over time in grades/subjects that discontinue testing vis-à-vis grades/subjects that are always tested. Our results show that eliminating testing did not have an impact on the likelihood of leaving teaching, changing schools within a district, or moving between districts. We only uncover small negative effects on the likelihood of grade switching. However, we do find relevant positive effects on retention of beginning teachers in the profession. In particular, the average probability of exit for teachers with 0-4 years of experience fell from 14 to 13 percentage points for teachers in grades 1 and 2 and from 14 to 11 percentage points in grades 6 and 7.

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Explaining the Gender Gap in STEM Attainment: Factors from Primary School to STEM Degree Completion

We investigate the determinants of high school completion and college attendance, the likelihood of taking science, technology, engineering or math (STEM) courses in the first year of college and the probability of earning a degree in a STEM field.  The focus is on women, who tend to be under-represented in STEM fields.  Tracking four cohorts of students throughout Florida, women perform nearly as well as men on math achievement tests through high school and are more likely to finish high school and attend college than males.  Among college students, however, women are less likely than are men to take courses in the physical sciences in their first year and are less likely to earn a degree in physics or engineering, even after adjusting for pre-college test scores.  Gender matching of students and math/science teachers in middle and high school tends to increase the likelihood that female college freshman will take at least one STEM course.  However, conditional on first-year coursework, neither gender matching at the secondary or college levels appears to have any effect on the likelihood of completing a major in a STEM field.  For all students, having high school math and physics teachers with a degree in math or physics, respectively, (as opposed to education) is associated with a higher likelihood of taking STEM courses as college freshmen. 

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