Psychosocial interventions to cultivate functional motivational beliefs in students are becoming increasingly popular. However, in education it is easy to prematurely place hope in promising, emerging techniques and ideas before they are fully explored through research. This study seeks to add to the body of knowledge examining psychosocial interventions by investigating one of the constructs popularly targeted in these interventions: self-theories of intelligence (STIs). Within this study, STIs are explored within a previously tested model of motivational variables (goal orientations, effort beliefs, interest, causal attributions, and failure response). The addition of metacognition to this model of achievement motivation is also investigated. Because research has suggested that STIs may be domain-specific, this study focused on STIs in the domain of science. Within this study, I used a self-report instrument comprised of seven subscales (each representing one motivational variable) to collect information on the achievement motivation of rural middle school students in the domain of science. Students from three schools in two counties in rural southwest Virginia participated in the study (n = 367). Independent and paired-samples t-tests, confirmatory factor analysis, mediational analyses, and structural equation modeling were used to answer the following four research questions. 1. To what extent are rural middle school students' self-theories of intelligence fixed or malleable in the domain of science? 2. To what extent do rural middle schools students have metacognitive knowledge and skills in the domain of science? 3. Does metacognition mediate the relationship between a malleable belief of intelligence and positive effort beliefs? 4. To what extent does the Blackwell, Trzesniewski, and Dweck (2007) model fit data obtained from rural middle school students in the domain of science? The results showed that the participants expressed a significant malleable view of intelligence, and demonstrated moderate amounts of metacognitive knowledge and skills. Metacognition was shown to be a significant mediator of STIs and effort beliefs. Standardized path coefficients for the achievement motivation model were significant; however, model fit indices revealed that this model may not be an adequate fit for these students' beliefs in the domain of science. / Ph. D.