This study concerns the influence of native language instruction in grades one through six on bilingual Hispanics' high school achievement. A nationally representative sample of 58,000 high school sophomores and seniors (the High School and Beyond data set) was used as the data source. Path analytic techniques were used to determine the magnitude of the effect of early native language instruction, while controlling for other relevant influences which included ethnic origin, mother's years in the United States, family background, intellectual ability, Hispanicity, English proficiency, and extent of native language instruction. Results suggest that the extent of native language instruction a bilingual Hispanic student receives has a negative influence on his or her later achievement. Other direct influences were ability, English proficiency, family background, mother's years in the United States (negative) and Hispanicity (negative). Results were consistent across different measures of extent of native language instruction. These preliminary and tentative results suggest that a transitional approach to bilingual education may be more fruitful than a maintenance approach. (CG)