This study analyzes data from multiple national representative samples to describe the status of curriculum tracking and ability grouping in middle and high schools and the effects on the following student groups: (1) African Americans; (2) Hispanic Americans; (3) American Indians; (4) Asian Americans; and (5) Whites. Statistical data from the following studies were analyzed: (1) High School and Beyond (HSB); (2) the National Longitudinal Study of the High School Class of 1972 (NLS); (3) the National Survey of Middle School Principals, 1988; and (4) the National Assessment of Educational Progress (NAEP) Young Adult Literacy Survey, 1986. The implications of the following findings are discussed: (1) racial/ethnic minorities are disproportionately distributed among tracks and ability groups; (2) the effects of tracking and ability grouping are especially negative for African American, Hispanic American, and American Indian students; (3) the effects of tracking and ability grouping are positive for Asian American students but have negative implications; and (4) 10-year trends reveal negative implications of tracking for White students. Alternatives to tracking and ability groups are suggested. A list of 15 references and eight tables of statistical data are appended. (FMW)