Large classroom configurations and lecture-centered pedagogy discourage student engagement. The advances in educational technology have empowered instructors to fill the gap. This study designed a digital question board (DQB) on digital canvas to facilitate student engagement in large lecture classes. A mixed-methods study with a quasi-experiment was conducted to investigate the influence of such intervention. The study was situated in an introductory research methodology course in a large comprehensive university in eastern China (n = 253). The quasi-experiment lasted for six weeks. The data from surveys, interviews, observations, and online posts were collected and analyzed. This study mainly presented qualitative analysis results from the exploratory approach. Eight themes emerged from 12 interviews, 161 survey responses and 457 student posts were discussed. It was found that following the proposed design principles, the presence of a DQB effectively facilitated students' cognitive and emotional engagement. The enhanced self-regulation and co-construction of knowledge all led to the improved cognitive engagement. The reduced social pressure of questioning and increased interactivity contributed most to their emotional engagement.