The purpose of this mixed methods study was to determine if consistent exposure to classroom pets in public elementary school classrooms affected children’s empathy. The sample included 44 students (females = 22; males = 22; mean age = 8.3 years) from four third-grade classrooms. A pre-test, post-test design was used to measure students’ empathy levels, and percentage changes in empathy scores were recorded for all groups. The sample was a convenience sample, and random assignment to treatment groups was not possible. Treatment included using classroom pet fish along with empathy-based lessons. Of the four participating classrooms, one classroom was the Control Group, with no classroom pet and no lessons. A second classroom was the Pet Only group (pet fish in the classroom, but no empathy-based treatment regimen). The third classroom was the Lessons Only group, which had no pet but the students engaged in a series of empathy-based mini lessons. The fourth classroom was the Pet+Lessons group, where students cared for, and interacted with, the classroom pet fish in addition to participating in a 4-week empathy-based treatment regimen. Each group participated in pre- and post-tests using the Bryant Index of Empathy for Children and Adolescents (Bryant, 1982), and the Lessons Only and Pet + Lessons group had four consecutive weeks of empathy-based mini lessons (each lesson with an opportunity for expansion through a project-based approach). This was followed by one week to reflect on the learning through final discussions and to re-administer the post-test. After exposure to the classroom pet and the empathy intervention, the three treatment groups all experienced an increase in empathy, while the Control Group experienced a decrease, suggesting that classroom pets, project-based empathy lessons, or a combination of both all had a positive impact on children’s empathy. Additionally, qualitative data in the form of interviews with classroom teachers, field notes from the researcher during empathy lessons, and examination of children’s empathy journals was analyzed to gain more knowledge on teacher and student perspectives of teaching and learning empathy and working with a classroom pet. Results are discussed relative to future research and classroom practices.