Modelling activities integrating construction and simulation supported explanatory and evaluative reasoning KingGretchen P. Bergan-RollerHeather GaltNicholas HelikarTomáš DauerJoseph T. 2019 <p>Model-based instruction offers numerous benefits to students, including increased content knowledge and critical thinking. This study explored the differences in the knowledge outcomes and reasoning processes employed by undergraduate students in an introductory biology lab as they constructed, revised, and simulated a computational model of a prokaryotic gene regulatory system. We analysed post-lesson conceptual models (<i>n</i> = 335) and audio-recorded small group discussions (<i>n</i> = 10) of students that either constructed and revised a computational model and then investigated a pre-constructed computational model or only investigated a pre-constructed computational model to determine the impact of constructing and revising a computational model. No significant differences were found between the mental models of students who constructed and revised a computational model and those who only simulated a pre-constructed computational model. However, this study demonstrated that constructing and revising a model before simulating it offered additional benefits to students by fostering deeper cognitive reasoning processes. Constructing and revising a model elicited more explanatory and evaluative reasoning and prompted students to discuss the underlying mechanisms of the biological system.</p>