This study is one of a series on cognitive behavior related to lingual types among Navaho children. The present work has aimed at gaining additional descriptive data regarding the effects of lingual types (compound bilinguals, Egnlish-speaking monolinguals, and Navaho-speaking monolinguals) on school achievement as measured by the Metropolitan Achievement Tests. Additionally, information was gained about (1) IQ score discrepancies resulting from the use of different types of tests, (2) the best predictors of school success, and (3) the effects of early English instruction. The following recommendations were made: (1) suitable, specific instruction in English should be provided Navaho children unfamiliar with the English language and culture preliminary to other school instruction; (2) in evaluating intelligence and learning ability of these children, measures should be used which motivate and accurately reflect ability or potential achievement; and (3) a curriculum for the early school years should be developed which incorporates the Navaho culture and heritage and involves wide use of Navaho teachers. The study includes some 14 tables for the presentation of statistical data and a list of references. For report of Phase 1, see ED 044 702. (Author/SK)