The aim of this paper is to investigate the most efficient ways to apply peer evaluation in writing courses, and a lack of studies on the views of students' experienced difficulties while responding to their peers' papers is the starting point of this paper. For this cause, the case study method was implemented, including an interview conducted with prep-class students (N=37) who attended a writing course for two semesters and a review of literature of related papers written over the past five years that specifically focuses on the ways to develop peer-evaluation skills of students. Both the interview and the relevant previous studies were analyzed through content analysis. As a result of the study, it was found that the challenges that students experienced were because of a lack of ability in language usage and having an avoidant personality, not having clear purposes for evaluation, a lack of ability in dominating the relevant terminology, and having difficulty in finding content and organization related mistakes. Consequently, students need effective training on peer evaluation to enhance their skills beforehand. The suggestions collected thanks to the literature review is expected to be helpful in this respect.