With the integration of computation into physics courses becoming more prevalent to adequately prepare our graduates for the workforce, there is a need for instructional and assessment materials for computational practices. In introductory physics courses, computation is typically used to model motion and so while loops are one of the first components of programs that students encounter. Our study examines and compares students' conception of the while loop following the completion of three computational problems and their engagement with the while loop in a new computational problem. We present three student cases who have similar conceptions of the while loop with aspects including its update function and the connection of lines of code in the while loop, specifically in how force, position, and momentum depend on each other. Despite their similar conception of the while loop, there is a variation in the outcomes of their engagement with the while loop in a new computational problem.