PurposeThis article explores the impact of systematically designed online collaborative activities in two engineering undergraduate modules and key considerations for student interaction in Moodle.Design/methodology/approachThe educational design research approach was chosen to improve educational practices through iterative needs analysis, design, development and implementation. The study followed design-based research (DBR) approach, with a mixed-method research design used to uncover the critical factors in designing, developing and implementing online collaborative learning activities for improving student interaction. Two iterative cycles of online collaborative learning activities were implemented using the Moodle learning management system for two modules of an engineering undergraduate degree programme at a state university in Sri Lanka.FindingsResults indicate that students had demonstrated increased motivation for collaborative activities, and they had not experienced any significant difficulties in accessing materials or instructions. This study emphasizes that the design of learning activities has a greater influence on determining the level of interaction between the learner interface and the learner content. Also, a higher number of interactions on the wiki page improved learner-learner interactions, likely due to clear instructions and reduced complexities compared to previous Moodle activities. Overall, appropriately designed online activities can enhance students' motivation and improve communication, collaboration, cooperation and a sense of community among peers.Research limitations/implicationsThe study's constraints included a small sample size of 93 students in two courses, which limits generalization of the results. The study's findings should be carefully considered before being applied to courses with nontechnical content. The second constraint was the number of courses on which the activities were carried out. The activities were designed specifically for two Earth Resources engineering courses, and the developed activities addressed technical course content. The effect of the activities on students' engagement and motivation in various courses with nontechnical content must be investigated, and a complete generalization of the study's results may be called into question. As a result, careful consideration must be given to generalizing the study's findings.Practical implicationsThe study found that authentic collaborative learning activities using online technologies increased student participation and helped them discover their engineering design skills. Future research can focus on developing activities for other technical courses and incorporating additional tools into the instructional process. The use of a design-based research approach was recommended for future studies to obtain more comprehensive results than traditional comparative study designs.Originality/valueThe findings of this study suggest mechanisms to improve student interaction through online collaborative activities, particularly for delivering technical content. Such an understanding of learner interactions with course content, peers, teachers and interfaces will assist in the effective transformation of traditional technical content to online delivery mode. This is a unique study of converting in-class delivered engineering module content to online delivery within an equal time frame under restricted facilities and conditions resulting from a pandemic environment.