Student self-report data from 933 Black middle school students and standardized mathematics test scores (SAT-10) were used to examine the relationship among student perceptions of teacher expectations and reform instructional practices, aspects of student motivation, and three student mathematics performance outcomes--time spent studying, expected grade in mathematics, and SAT-10 Math scores. Structural equation modeling was used to examine the influence of the teacher variables on student outcomes, as mediated by student motivation. Students who reported greater teacher use of reform practices and higher teacher expectations showed more desirable levels of motivation to learn mathematics. Teacher use of reform practices and higher teacher expectations had direct effects on SAT-10 scores, as well as indirect effects on all three mathematics outcomes examined mediated through the three aspects of student motivation. Finally, multiple squared correlations revealed meaningful proportions of variance explained in student motivation and mathematics outcome variables ranging from 4% to 29%. (Contains 11 footnotes, 4 tables, and 1 figure.)