Dynamic Visualization in Animated Mathematics Videos: Students’ Experiences and Learning Outcomes

University students increasingly watch animated math videos that use dynamic visualizations as part of their learning process. Despite students' positive appreciation, little is known about how these visualizations contribute to learning outcomes. This paper examines the relationship between learning outcomes and students' experiences with dynamic visualizations in animated math videos, drawing on visualization research by Presmeg (2014) and Arcavi (2003), as well as a recent taxonomy by ten Voorde et al. (2024). We investigate how dynamic visuals in various didactic roles impact the learning outcomes and experiences of university calculus students. Two sessions, each involving approximately 20 students, featured calculus-themed animated videos from the YouTube channel 3Blue1Brown. Pre-and post-tests assessed learning outcomes, while questionnaires classified student experiences. Our findings indicate that while students learn from dynamic visualizations, they often overestimate their effectiveness. Explicit recognition of a visual's learning goal is associated with improved learning and appreciation. Students report that dynamic visuals foster visual imagery, support understanding, and guide attention. However, they can also hinder learning, especially when they do not align with clear learning goals.