This teaching note describes the use of anonymous, online, graded, peer review in an undergraduate social work human behavior in the social environment writing-intensive course. Students (N=37) provided written feedback describing their learning from writing and receiving peer reviews. Students identified learning from receiving the peer reviews, improving their writing through the identification of their own common writing errors, and developing a better understanding of the writing process, as well as learning gained from writing peer reviews, including learning from viewing others' writing assignments and developing the ability to provide feedback to peers that is both supportive and constructive. Implications for social work instructors are described, including grading peer reviews, providing guidelines for peer reviewing, being transparent about the perceived benefits of peer reviewing for students, and using online course technology to complete peer reviews outside of class, decreasing the amount of in-class time required.