Effects of Curricular Differences on Achievement Test Data at Item and Objective Levels

Abstract

The objectives of this study were to examine the impact of different curricula on standardized achievement test scores at item and objective levels and to determine if different curricula generate different patterns of item factor loadings. School buildings from a middle-sized district were rated regarding the degree to which their curricula matched the content of the standardized test, and the actual textbook series used within each building (classroom) was determined. Covariate analyses of objective scores and plots and correlations of item p values indicated very small, nonsignificant differential effects across ratings and textbook series. Factor patterns indicated no curricular effects on large first factors. These findings parallel the results of a previous study conducted at the subtest level. We conclude that educators need not be unduly concerned about the impact of specific and generally small differences in curricular offerings within a district on standardized test scores or inferences to a broad content domain.