EthnicallyDiverseStudents'KnowledgeStructuresin First-SemesterOrganicChemistry

Chemistry courses remain a challenge for many undergraduate students. In particular, first- semester organic chemistry has been labeled as a gatekeeper with high attrition rates, especially among students of color. Our study examines a key factor related to conceptual understanding in science and predictive of course outcomes—knowledge structures. Previous research on knowledge structures has focused on differences between experts and novices. Given the increasing ethnic diversity of college classroomsandresearchindicatinguniquedifferencesincertainhigherordercognitiveprocessesassociated cultural practices and ethnicity, it is important to investigate whether similar patterns exist with respect to knowledge structures. Our study utilized concept maps to measure knowledge structures. Two separate analyseswhereperformedtodeterminewhetherornotethnicallydiversestudents'organizetheirknowledge of organic chemistry content in structurally different ways. The first analysis utilized concept map proposition scoring to examine the influence of prior science achievement and ethnicity on knowledge structures. The second analysis examined holistic map structures to determine whether or not ethnically diverse students show qualitatively distinct structures overall. Results show significant mean differences on concept map proposition scores related to both prior science achievement and ethnic group membership. However,examinationofholisticstructuresrevealedthatstudents'qualitativeholisticstructuresdidnotvary by ethnic group membership. Taken together, our findings suggest that variation in students' knowledge structures are related to prior science achievement across ethnic groups, not qualitative differences in the ways ethnically diverse students' structure knowledge. Implications for teaching and learning in organic chemistryarediscussed. # 2014 Wiley Periodicals, Inc. J Res Sci Teach 51: 741-758, 2014