A study analyzed the degree to which an African American verbal tradition (Black English Vernacular) survives in the writing of Black students across a generational time span. A total of 867 essays from the 1984 and the 1988/89 National Assessment of Educational Progress (NAEP) were subjected to primary trait and holistic scoring analysis, and were ranked in terms of the degree of African American discourse. These scores were compared to the scores given by NAEP raters, and to scores from the 1969 and 1979 NAEP. Results indicated that: (1) no correlation existed between a discernibly African American discourse style and the production of BEV syntax, supporting results of earlier studies of 1969 and 1979 NAEP essays; (2) the more discernibly African American the discourse, the higher the primary trait and holistic scores, and the less discernibly African American the discourse, the lower the primary trait and holistic scores, contrary to earlier studies; and (3) "imaginative/narrative" essays continued to be Black students' strong suit. Findings suggest that students who employed a Black expressive discourse style received higher NAEP scores than those who did not. Recommendations for writing instructors include: capitalize on the strengths of African American cultural discourse; encourage students toward the field dependency style, which enables them to produce more powerful, meaningful, and more highly rated essays; and deemphasize concerns about BEV grammar. (Two figures listing NAEP scoring criteria, a figure listing Black English variables, and two tables of data are included; 37 references, an appendix of data, and six sample essays are attached.) (RS)