The evidence of a general achievement gap, and more specifically, a reading gap between African American students and White students is a well documented and alarming phenomenon (Chatterji, 2006; Darling-Hammond, 2004, 2007; Darling-Hammond, Holtzman, Gatlin & Heilig, 2005; Fishback & Baskin, 1991; Jencks & Phillips, 1998; Haycock, 2001; Ladson-Billings, 2006; Lindo, 2006). Factors such as equal access to the high quality schools, negative teacher attitudes and test bias and other possible sources of inequality have been suspected as sources of the cause of the achievement gap (Darling-Hammond, 2004; Goodman & Buck, 1973). Research is equivocal on which factors most contribute to the difficulty many African American children have matching the performance levels of their White peers. However, new theories on children's use of non-mainstream American English as it relates to their achievement are emerging. Therefore, the purpose of this study is to investigate the language and literacy skills of students who use non-mainstream American English, to better understand the mechanisms influencing achievement and to investigate possible causes that may be contributing to the continuation of this disparity. Hierarchical linear modeling and descriptive statistics were used to analyze the data. Three main findings emerged: (1) the results on Part 1 of the DELV-S, which identifies variation from MAE generally follow patterns observed in the extant literature (e.g., African American children are more likely to use a dialect that varies from MAE than are White children); (2) Children who speak NMAE in First grade generally use fewer of the phonological and morphosyntactic features of their dialect at the end of First grade than they did in the fall; and (3) Children who use fewer NMAE features (or more MAE features) in the fall of first grade tend to show greater literacy skill gains than do children who use more NMAE features. The results of this study help build convergence toward understanding the relationship between children's use of NMAE and their language and literacy development and achievement. Specifically, this study adds to the growing literature base that supports children's linguistic flexibility as the most likely theory elucidating the complexity of language and reading development. In addition, if offers possible reasons for the difficulty encountered by NMAE speaking children learning to read.
