This dissertation is presented in multiple article format with an introduction, a literature review, a design case, a mixed methods study, and a conclusion. The literature review outlines important concepts and theories that appear in subsequent manuscripts. The design case describes the seven-year design process that resulted in the online physical education app, a tool used in online physical education classes to monitor student progress toward heart rate goals. The mixed methods study investigates student attribution of outcomes observed in the physical education app. These manuscripts present both a long-term iterative design process and an empirical research study to better understand how students use their own data to inform and shape their learning. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]