This study was designed to determine changes in the mathematics achievements and goal orientations among disadvantaged students after instructional intervention in textbook transformation and instructional intervention for disadvantaged students. There were eight disadvantaged students in this instructional intervention. Factor analysis, MANOVA, and covariance analysis were used in data analysis. Several important findings were discovered. First, prior to instructional intervention, the achievement goal orientations of disadvantaged students were no different from those of other students, but their mathematics achievements were lower than those of others. Second, after instructional intervention, the achievement goal orientation of disadvantaged students became higher. Finally, after instructional intervention, the mathematics achievements of disadvantaged students became higher, too. [ABSTRACT FROM AUTHOR]