Navajo school students, it is believed, underachieve at school in terms of school attendance, dropout rates, and standardized performance tests. Among the many reasons proposed to explain the persistent school underachievement is that school culture is largely based on individualism, interpersonal competition, and other Western norms and values. These, it is argued, are an anathema to Native Americans. Hence, school culture may predispose many Navajo High School students to failure. To test this belief I constructed a model of school achievement motivation drawn from Western conceptualizations of achievement motivation described Navajo High School students achievement motivation. Using confirmatory factor analyses tests of equivalency were conducted that contrasted non-traditional Navajo students and females with near traditional Navajo students and males. Using structural equation modeling, I examined the relations of the language, location, and gender variables on the achievement goal factors, mediated by school measures of achievement, ability beliefs, social goals and achievement goals. I concluded that non-traditional and near traditional Navajo students are more similar than dissimilar. Clearly this raises concerns regarding the making of policy based on assumptions regarding presumed differences between non-traditional and near traditional Navajo High School students. I also concluded that, school achievement measures, the ability beliefs, and the social approval and social concern goals are important factors that influence the school achievement goals Navajo students emphasize. This has implications for the manner in which schools and teachers emphasize these factors in classrooms. / Doctor of Philosophy (PhD)