A comparison of mathematics achievement by gender, socio-economic status, and ethnicity in departmentalized and self-contained elementary school organizational structures

The purpose of this study was to examine the differences in mathematics achievement scores among elementary school students placed in departmental and self-contained classroom organizational structures. Previous research on the effects of organizational structures on student achievement has been inconclusive due to several confounding variables. Thus, this study considered the effects of ethnicity, gender, and socio-economic status (SES), while comparing the differences between these two organizational structures on mathematics achievement. A sample of 21, 454 fifth grade students from 202 elementary schools in a large, urban public school system participated in the study. The measure of mathematics achievement was the Florida Comprehensive Assessment Test-Norm Referenced Test. A 2 x 2 x 3 x 2 factorial analysis of variance (ANOVA) design was used.; The four-way ANOVA showed statistically significant main effects for SES and ethnicity, but not for organizational structures and gender. However, there were significant interactions with organizational structures and ethnicity, organizational structures and gender, organizational structures and SES, and gender and ethnicity. To determine the relative effects of SES and ethnicity in relation to organizational structures, a series of three ANCOVAs were performed. In the analysis with SES covaried, organizational structure was statistically significant, but did not account for a significant amount of variance in mathematics scores and was not statistically significant in the analyses with ethnicity controlled. When both SES and ethnicity were controlled, each accounted for 4.5% of the variance in mathematics scores independently, and 9.5% together. There were significant interactions with organizational structures and ethnicity, organizational structures and gender, organizational structures and SES, and gender and ethnicity. However, no more than 12% of the variance in mathematics scores was ever accounted for and the effect sizes for organizational structure were minimal. While there was some evidence that scores were slightly higher for the departmentalized structure, the differences were negligible from a practical point of view and disappeared when SES and ethnicity were controlled. Therefore, when making educational decisions regarding organizational structures, caution should be taken.