Having students actively engaged with each other in discussions has become an increasingly important and common aspect of the classroom environment. This increased emphasis has also meant that instructors need to find ways to effectively and efficiently evaluate class participation. In this paper, we describe the most common method used for these assessments and highlight some of its inherent challenges. We then propose an alternative method based on peer nominations. Two case studies illustrate the advantages of this method; we find that it is both easy for students to complete and provide instructors with valuable diagnostic information with which to provide feedback and assign grades. (Contains 4 tables and 4 notes.)