Interest in engineering at early stages of the educational career is one important precursor to choosing to study engineering in college, and engineering-related clubs are designed to foster such interest and diversify the engineering pipeline. In this study, the researchers employed a social cognitive career theory framework to examine level of interest in studying engineering and expected educational attainment among underrepresented low-income middle and high school students participating in materials science and engineering (MSE) clubs. Questionnaire data were collected from over 200 MSE club participants in low-income public middle and high schools in Puerto Rico. The results indicate that perceived value of engineering is useful in predicting career interest among underrepresented middle and high school students; however, traditional predictors of educational interests and attainment (gender, mother's education, parent expectations) exert the strongest influence on engineering interest and attainment expectations.