We discuss two proof evaluation activities meant to promote the acquisition of learning behaviors of professional mathematics within an introductory undergraduate proof-writing course. These learning behaviors include the ability to read and discuss mathematics critically, reach a consensus on correctness and clarity as a group, and verbalize what qualities "good" proofs possess. The first of these two activities involves peer review and the second focuses on evaluating the quality of internet resources. All of the activities involve groupwork and reflective discussion questions to develop students' experience with these practices of professional mathematics.