Concerns about student resegregation resulting from discriminatory student grouping practices are highlighted in this paper. Part 1 determines the characteristics of discriminatory ability grouping and tracking practices through a content analysis of 35 Office for Civil Rights (OCR) case file documents for the fiscal years 1983-89. Twenty-three out of 35 investigations used disparate impact analysis. Explanations are offered for how the OCR uses disparate impact analysis and disparate treatment analysis and reasons why the OCR found ability grouping to be discriminatory. The second part assesses the extent to which ability grouping is discriminatory in the nation's elementary and secondary schools through an analysis of national survey data conducted by the Center for Research on Elementary and Middle Schools (CREMS) and the OCR. Findings indicated a disproportionate number of racially identifiable classes. The third part formulates policy recommendations and concludes that disagreement exists between the General Accounting Office and Department of Education on providing federal guidance to student and local education agencies. One table is included. Appendixes explain the OCR's discretion for using disparate treatment or impact analysis and provisions on ability grouping in the Emergency School Aid Act. (21 footnotes) (LMI)