Research acknowledges that learners' motivation and self-regulation benefit their academic growth, and it applies to writing development. However, limited research has investigated how learners are supported to foster motivation and cultivate self-regulated learning strategies in writing classrooms. Drawing upon data from semi-structured interviews, self-reflections, and developing drafts, this qualitative case study examined how six first-year EFL university students with previous exam-focused writing experience developed motivation and employed selfregulated learning strategies in writing in a year-long English writing course designed based on the socio-constructivist approach. Analysis revealed that the participants experienced positive changes in writing motivation, including enhanced task interest, clarified outcome expectations, refocused goal orientation, and increased self-efficacy in writing, as they engaged in interrelated social and collaborative writing activities. They also used various self-regulated learning strategies, including cognitive strategies, goal setting, self-evaluative standards, self-selected models, and mental imagery, to improve writing skills and navigate writing. The study provides implications for researchers and practitioners in EFL writing within exam-oriented contexts.