The current study examines the relative impact of take home (open book) examinations (THE) and in class (closed book) examinations (ICE) on student academic performance and wellbeing outcomes. Specifically, this study contributes to our understanding about students' long-term knowledge retention, measured four to six months after completing the course. A unique longitudinal dataset consisting of four cohorts of a social science bachelor and master course that implemented either a THE or ICE in successive years was used. Survey data included wellbeing and academic performance measures as well as a 10-item knowledge retention quiz. Within the master course, the ICE cohort had higher examination grades and higher knowledge retention scores than the cohorts that completed a THE. In the bachelor course, there were no differences in knowledge retention across cohorts. Examination score was associated with higher knowledge retention scores across both courses. One bachelor cohort reported lower wellbeing compared to others (cohort 2021-2022); however, we found no further differences in academic or wellbeing outcomes based on examination form. The findings suggest a slight advantage of ICEs over THEs with regard to academic performance.