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Helen F. Ladd

Wes Austin, Bengie Chen, Dan Goldhaber, Eric A. Hanushek, Kris Holden, Cory Koedel, Helen F. Ladd, Jin Luo, Eric Parsons, Gregory Phelan, Steven G. Rivkin, Tim Sass, Mavzuna Tureava.

Anecdotal evidence points to the importance of school principals, but the limited existing research has neither provided consistent results nor indicated any set of essential characteristics of effective principals. This paper exploits extensive student-level panel data across six states to investigate both variations in principal performance and the relationship between effectiveness and key certification factors. While principal effectiveness varies widely across states, there is little indication that regulation of the background and training of principals yields consistently effective performance. Having prior teaching or management experience is not related to our estimates of principal value-added.

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Robert C. Carr, Tyler Watts, Jade M. Jenkins, Yu Bai, Ellen S. Peisner-Feinberg, Clara G. Muschkin, Helen F. Ladd, Kenneth A. Dodge.

Prior research has found that financial investments in North Carolina’s pre-kindergarten (pre-K) program generated positive effects on student reading and math achievement through eighth grade (Bai et al., 2020). The current study examined the interaction between NC Pre-K funding and two key dimensions of the subsequent educational environment students experience in their school districts: average achievement and achievement growth. In relation to student reading and math achievement in eighth grade, the benefits of NC Pre-K funding were found to be additive to the benefits of school-district average achievement. The benefits of NC Pre-K funding were also found to interact with the benefits of school-district achievement growth such that the NC Pre-K effect was larger in school districts with lower rates of growth in academic achievement. These findings suggest that public investments in early childhood education may be particularly beneficial in the long term for children who subsequently experience low-growth schooling environments compared to children in high-growth environments.

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Charles T. Clotfelter, Helen F. Ladd, Calen R. Clifton.

Using detailed classroom-level data for North Carolina, we build on previous research to examine racial gaps in access to high-quality teachers. We calculate the exposure of White, Black and Hispanic students to teachers with various characteristics in 4th grade, 7th grade math and English, and 10th grade math and English. We find that across the state White students enjoy sizable advantages over both Black and Hispanic students in the form of higher exposure to teachers with strong credentials and lower exposure to teachers with weak credentials. Remarkably, we also find this pattern of White advantage in most individual counties, with the largest White advantage occurring in the largest counties by enrollment. A decomposition of the White advantages shows that the bulk of them can be attributed to differences across counties and differences between schools within counties. Only in 10th grade are differences across classrooms within schools important in explaining the White advantage.

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Charles T. Clotfelter, Steven W. Hemelt, Helen F. Ladd, Mavzuna Turaeva.

The decades-long resistance to federally imposed school desegregation entered a new phase at the turn of the new century, when federal courts stopped pushing racial balance as a remedy for past segregation, adopting in its place a color-blind approach in judging local school districts’ assignment plans. Using data that span 1998 to 2016 from North Carolina, one of the first states to come under this color-blind dictum, we examine the ways in which households and policymakers took actions that had the effect of reducing the amount of interracial contact in K-12 schools within counties. We divide these reductions in interracial contact into portions due to the private school and charter school sectors, the existence of multiple school districts, and racial disparities between schools within districts and sectors. For most counties, the last of these proves to be the biggest, though in some counties private schools, charter schools, or multiple districts played a deciding role. In addition, we decompose segregation in the state’s 13 metropolitan areas, finding that more than half can be attributed to racial disparities inside school districts. We also measure segregation by economic status, finding that it, like racial segregation, increased in the largest urban counties, but elsewhere changed little over the period.

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Helen F. Ladd, Edward B. Fiske.

Because of the many special characteristics of charter schools, policy makers who aim to promote a system of charters schools that ensures fair access to, and fair treatment of, disadvantaged students will need a public accountability system oriented, at least in part, to equity concerns. Massachusetts, with its single statewide authorizer, as well as its system of periodic site visits to schools and specific performance criteria, illustrates such a system. In this paper, we first explain why an equity-oriented approach is important. We then describe and evaluate the Massachusetts approach, with particular attention to the information provided by the periodic site visits. Although Massachusetts does not fully succeed with all its charter schools, especially with respect to fair treatment, it is hard to make the case that charter schools will be beneficial for disadvantaged students in the absence of an accountability system of this type.

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Charles T. Clotfelter, Helen F. Ladd, Calen R. Clifton, Mavzuna Turaeva.

Using detailed administrative data for public schools, we document racial and ethnic segregation at the classroom level in North Carolina, a state that has experienced a sharp increase in Hispanic enrollment. We decompose classroom-level segregation in counties into within-school and between-school components. We find that the within-school component accounted for a sizable share of total segregation in middle schools and high schools. Recognizing its importance could temper the praise for school assignment policies that reduce racial disparities between schools but allow large disparities within them. More generally, we observe between the two components a complementary relationship, with one component tending to be large when the other one is small. Comparing the degree of segregation for the state’s two largest racial/ethnic minority groups, we find that White/Hispanic segregation was more severe than White/Black segregation, particularly within schools. Analyzed as separate administrative units, schools with large shares of Black students tended to have more White/Black segregation across classrooms than schools with smaller shares. Finally, we examine enrollment patterns by course and show that school segregation brings with it differences by race and ethnicity in the courses that students take, with White students more likely to be enrolled in advanced classes.

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Helen F. Ladd, Mavzuna Turaeva.

We use information on the charter school choices made by North Carolina families, separately by race, who switched their child from a traditional public school (TPS) to a charter school in 2015-16 to explore how such choices affect racial segregation between schools and racial isolation within charter schools. We find that the movement of white switchers, but not minority switchers to charter schools increases racial segregation between schools. In addition, using a conditional logit model to estimate revealed preferences, we find that the value parents place on the racial composition of individual charter schools differs by the race and income of the switchers. As a result, even after we control for other valued aspects of charter schools -- such as distance from the previous traditional public school and the charter school’s mission, academic performance and services offered -- the differential preferences of the switchers leads to substantial racial isolation within charter schools.

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Lucy C. Sorensen, Helen F. Ladd.

High teacher turnover imposes numerous burdens on the schools and districts from which teachers depart. Some of these burdens are explicit and take the form of recruiting, hiring and training costs. Others are more hidden and take the form of changes to the composition and quality of the teaching staff. This study focuses on the latter. We ask how schools respond to spells of high teacher turnover, and assess organizational and human capital effects. Our analysis uses two decades of administrative data on math and ELA middle school teachers in North Carolina to determine school responses to turnover across different policy environments and macroeconomic climates. Based on models controlling for school contexts and trends, we find that turnover has marked, and lasting, negative consequences for the quality of the instructional staff and student achievement. Our results highlight the need for heightened policy attention to school specific issues of teacher retention.

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