A time-series analysis was used to investigate Arabic undergraduate students' (n = 50) perceptions of assessed group work in a major government institution of higher education in Qatar. A longitudinal mixed methods approach was employed. Likert scale questionnaires were completed over the duration of a collaborative writing event. Additionally, open-ended questionnaires were administered after the students received their grade for their term paper. This study found that the participants' perceptions were positive towards assessed group work throughout the duration of the event, changed in a statistically significant way after the submission of the first piece of formally assessed work, and are temporal and liable to change depending on what is experienced. The results of this study suggest that: assessed collaborative writing is a feasible pedagogical tool within higher education; undergraduate learners place value on group work as it enables them to collaboratively generate, share and develop their ideas; and researchers who investigate perceptual or attitudinal changes should consider whether their study requires time-sensitive methodology.