Christina Clark Tuttle

Student Selection, Attrition, and Replacement in KIPP Middle Schools

Skeptics of the KIPP (Knowledge Is Power Program) charter school network argue that these schools rely on selective admission, attrition, and replacement of students to produce positive achievement results. We investigate this using data covering 19 KIPP middle schools. On average, KIPP schools admit students disadvantaged in ways similar to other local students, and attrition patterns are typically no different at KIPP than at nearby schools. Unlike district schools, however, KIPP schools tend to replace students who exit with higher achieving students, and fewer students are replaced in the later years of middle school. Overall, KIPP’s positive achievement impacts do not appear to be explained by advantages in the prior achievement of KIPP students, even when attrition and replacement patterns are taken into account.

Do KIPP Schools Boost Student Achievement

The Knowledge Is Power Program (KIPP) is an influential and rapidly growing nationwide network of charter schools serving primarily disadvantaged minority students. Prominent elements of KIPPs educational model include high expectations for student achievement and behavior, and a substantial increase in time in school. KIPP is being watched closely by policy makers and educators as a possible model for urban education, but existing studies of KIPPs effects on students have been subject to methodological limitations, making them less than conclusive. We measure the achievement impacts of forty-one KIPP middle schools across the country, using propensity-score matching to identify traditional public school students with similar characteristics and prior-achievement histories as students who enter KIPP. We find consistently positive and statistically significant impacts of KIPP on student achievement, with larger impacts in math than reading. These impacts persist over four years following admission, and are not driven by attrition of low performers from KIPP schools.