Employers now consider teamwork one of the essential skills for students to acquire during their academic life. However, COVID-19 has accelerated the transition towards online learning, affecting how we work in teams. This study looked at how scaffolding socially shared regulation of learning can influence teamwork in an online, project-based course. Intra-group peer assessment was used to analyze three variables during a first-year engineering course. By following the proposed scaffolding, students found an optimum balance in their contribution to team meetings. They also managed to establish a positive working environment earlier in the semester. This study contributes to the field by showing that scaffolding socially shared regulation in an online, project-based course allows for an interplay between collaboration during class and cooperation outside of it. This interplay ultimately leads teams to achieve better results on their final project.