The aims of this study were to investigate the level of cognitive development of Afro-American students enrolled in general chemistry courses at the college level and to determine the strategies used by both successful and unsuccessful Afro-American students in solving specific types of stoichiometric problems. It was found that the choice of a strategy is not significantly related to cognitive development of the student in specific types of stoichiometric problems. However, the following trend was noted: Students who are formal-operational in thought are more likely to be successful when solving mole-volume problems and complex mole-mole problems than are their concrete-operational counterparts. Additionally, a systematic strategy proved to be successful for the students, regardless of the cognitive development, when balancing simple and complex chemical equations. Also, algorithmic/reasoning strategies were needed to solve the mole-volume problem. A higher level of cognitive development and reasoning may be crucial factors in solving the more sophisticated types of problems in stoichiometry.