To support and improve effective science teaching, educators need methods to reveal student understandings and misconceptions of science concepts and to offer all students an opportunity to reflect on their own knowledge construction and organization. Students can benefit by engaging in scientific activities in which they build personal connections between what they learn and their own experiences. Integrating student-constructed digital concept mapping into the science curriculum can reveal to both students and teachers the conceptual organization and understanding of science content, which can assist in building connections between concepts and personal experiences. I used a qualitative case study research design in which my setting was one third-grade classroom. Participants were the teacher and student in this classroom. This paper describes how a class of third grade students used concept maps to understand science concepts (specifically, "watershed systems"). During class discussions and interviews students revised concept map content and structure as their ideas developed. The results of this study demonstrated how students' understandings and misconceptions were revealed through their construction of digital concept maps over time. Each new concept map built upon the previous one for a total of seven maps per student. Analyses of the concept maps using an evaluative rubric revealed changes over time in concept map structure and content. A formal assessment of watershed concepts was administered four times during the course of the science unit. I conclude that my research model used for integrating concept maps in this science class enabled students to reflect deeply on their work and to accurately revise their knowledge construction and content. Using concept maps to inform her teaching, the teacher also made robust use of the research model. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]