Purpose: In order to provide developmental guidelines for predicted dialect differences, trends in the use of features contrastive between General American English (GAE) and African- American English (AAE) were explored in a representative, national sample. Method: Participants were 1130 AAE- and 194 GAE-speaking typically-developing children, ages 4 to 12. A core set of distinguishing developmental features were identified and used in a focused elicitation of contrastive items in obligatory contexts. Responses were analyzed for age-related changes and demographic influences. Results: Major findings include pervasive use of zero-marked forms and predicted substitutions in young typically-developing AAE speakers through age 6. After age 6 the pattern was reversed: levels of zero-marking were lower than overt-marking, but remained distinct from GAE levels of similar forms. Moreover, total absence of overt-marking after age 7 was a-typical. Increased use of overt-marking and other GAE-like forms was observed earlier for constructions like multiple negation and regular past tense /–ed/ than invariant subject-verb agreement (e.g., she run). Parent education and region, but not gender, were significant, but small factors influencing contrastive feature use. Conclusion: Expected contrastive feature shifts were distinguished from general language development and possible clinical indicators.