Computer simulation users can freely control operational factors and simulation results, repeat processes, make changes, and learn from simulation environment feedback. The focus of this paper is on simulation-based design tools and their effects on student learning processes in a group of 101 Taiwanese senior high school students. Participants identified as having executive, legislative, judicial, global or local thinking style tendencies were asked to design bridges using WPBD2007 computer simulation freeware. Design strategies and design tool usage were video recorded and analyzed. Results indicate a positive correlation between judicial thinking style and frequency of substantial change in structure and goal strategy; a negative correlation between local thinking style and frequency of component tool list usage; a negative correlation between use of top-down strategies and frequency of using two types of assistance tools; a positive correlation between the use of bottom-up strategies and frequency of using both tool types; a positive correlation between the use of a substantial change strategy and frequency of using the graphical interface only; and positive correlations between total construction costs and the frequencies of using the substantial change strategy and component list tool.