Working on an open-ended task such as designing an engineering artifact is a rich learning experience for students, although they generally receive little direct guidance and instruction from their professors. In order to be successful on such a task, students need to set reasonable goals for themselves and adopt intrinsic standards for success so that they will be able to solve problems strategically. Many studies have found that students' cognitive and metacognitive skills play an essential role in such problem solving processes. This study attempts to further one's understanding of the use of metacognitive skills of students who engage in an open-ended team-based design project. It aims to examine learners' self-management of cognition by observing a group of four undergraduate engineering students exercising their executive control over behavior during their work on their senior design project class. The findings of this study enhance and support pre-existing assumptions on how typical engineering students engage in a team-based project. In regard to these findings, the discussion focuses on two things: (1) the work categories that reflect all mental and physical activities during the project; and (2) the important knowledge to metacognition during the project. (Contains 3 figures and 1 footnote.)