Unprecedented investments are being made in mathematics tutoring interventions for K-12 students, but results from these interventions are not always promising. Traditional online or distance math tutoring can treat learning as disembodied, and not give learners access to embodied resources like gestures, movements, and actions. Virtual Reality offers important opportunities for students joining from a distance to utilize virtual bodies in a fully immersive world, where students can also interact with dynamic mathematical objects. In the present study, we examined 20 middle school students engaging in a VR-based distance tutoring intervention over 7 weeks. We found some preliminary promising indications for the effect of the intervention on students' mathematical learning, compared to a control group which received VR-based tutoring in English-Language Arts. By systematically qualitatively coding videos of students and tutors engaged in math tutoring, we identified affordances of the VR environment--including the use of gestures and whole-body movements related to students' mathematical reasoning, the presence of mathematical play in the environment, and unique interactions with dimensionality in the 3D space. We also found important constraints from our thematic coding of the interactions in the videos--including connection problems, issues with spatial orientation and virtual body positioning, and off-task or distracted students in the VR environment. We close with recommendations for future VR-based tutoring interventions.