Online math videos for student learning are abundant; yet they are surprisingly uniform in their monologic, expository mode of presentation and their emphasis on procedural skill. In response, we created an alternative model of online math videos that feature the unscripted dialogue of secondary school students, who convey sources of confusion and resolve the dilemmas that arise during problem solving. Each video shows a pair of students (called the talent) next to their mathematical inscriptions, which allows other students viewing the videos (called vicarious learners) to clearly see both the talent and their work. Previous research has conceptualized vicarious learners as epistemically-detached spectators. In contrast, we found that the vicarious learners who participated in this study took an emotionally-involved, quasi-collaborative stance toward the talent in the dialogic online math videos.