In 1997, Lindamood-Bell Learning Processes partnered with Pueblo School District 60 (PSD60), a heavily minority urban district with many Title I schools, to implement a theoretically based initiative designed to improve Colorado Student Assessment Program reading scores. In this study, the authors examined achievement in Grades 3-5 during the years 1998-2003. PSD60 schools and schools statewide were compared through a series of repeated measures analyses of covariance controlling for school size, percentage of minority students enrolled, socioeconomic status, and the amount of time a school was included in the intervention. Statistically significant and increasing gains favoring the Lindamood-Bell reading intervention were found both overall and in analyses of Title I schools.