Aesthetics of a Learning Management System (LMS) user interface can be a very powerful tool for supporting learning, yet it is the least considered issue in design. This embedded experimental study researches the differences in perceived aesthetics of web and mobile interfaces of an LMS and the opinions of students about the effect of these differences on their learning. The data was gathered from a total of 128 students of a public university. The data collection instruments where, (i) Visual Aesthetics of Websites Inventory (VisAWI) for collecting quantitative data, and (ii) individual interviews with a sample of 10 students completing the inventory. This study reveals that learning materials presented in mobile devices might need design methods specific for mobile interfaces and it might have a positive impact on student learning.