Background and Context: GitHub has been recently used in Software Engineering (SE) classes to facilitate collaboration in student team projects as well as help teachers to evaluate the contributions of their students more objectively. Objective: We explore the benefits and drawbacks of using GitHub as a means for team collaboration and performance evaluation in large SE classes. Method: Our research method takes the form of a case study conducted in a senior level SE class with 91 students. Our study also includes entry and exit surveys, an exit interview, and a qualitative analysis of students' commit behavior. Findings: Different teams adapt GitHub to their workflow differently. Furthermore, despite the steep learning curve, using GitHub should not affect the quality of students' submissions. However, using GitHub metrics as a proxy for evaluating team performance can be risky. Implications: We provide several recommendations for integrating Web-based configuration management tools in SE classes.