Participating in online mathematical discussions is a beneficial strategy to improve online math learning. Research has examined online mathematical discussions from various aspects, focusing on the content discussed, student interaction, and the technical tools facilitating student participation, but few studies have investigated the interplay among these aspects. This study draws on Communicative Ecology Theory (CET, Foth & Hearn, 2007), which conceptualizes the sustainability of online communities as influenced by discursive, social, and technical factors, to explore how students’ discursive, social, and technical participation behaviors on an online mathematical discussion board are interacted. Leveraging a dataset including more than 90,000 students and two million online discussion interactions, this study indicated that students’ engagement with technical functions, especially a communication tool and a motivation system, within the discussion board significantly facilitated their social interactions and enhanced their demonstration of mathematical knowledge, mathematical literacy, and affective control in the discussions. These findings provide insights for educators and designers of educational applications to enhance student participation in online discussions thereby improving the effectiveness of these discussions in online learning.