School mobility and student achievement in an urban setting

Many studies show negative relationships between school or geographic mobil ity and school achievement. However. two longitudinal studies show no relat ionship between mobility and subsequent achievement when prior achievement is controlled. The present study replicates both findings among 764 sixth-g rade students in a mobile school district in New York City, with mobility d efined by school changes, achievement assessed with standardized tests and age-grade progress, and eligibility for free or reduced price lunches (an e conomic indicator) controlled. Total mobility was related to sixth-grade ac hievement when earlier achievement was not controlled, but mobility after t hird grade was not related to sixth-grade achievement when third-grade achi evement was controlled. Some authors suggest that a third variable, such as family background, accounts for both inability and achievement. We provide evidence for a different explanation. Early mobility (prior to third grade ) was a more potent predictor of sixth-grade achievement than later mobilit y. (C) 2000 John Wiley & Sons, inc.