Retention of students in Science, Technology, Engineering and Mathematic (STEM) degrees is declining and it has been suggested that undergraduate research experiences early in students’ collegiate careers may increase this trend. We developed an animal behavior research course for freshman and sophomores, and found that students enrolled in this course had improved opinions, learning gains, and attitudes towards science. We also found numerically higher STEM retention in students enrolled in this course (98.1%) compared to college and university-level STEM retention data. Descriptive feedback from the students also indicated that they enjoyed their research experience and that the experience generated enthusiasm for research and scientific careers. These results suggest that this course may be a good working model for further undergraduate research courses at other institutions and may keep students interested in STEM careers.