In addition to stimulating interest through experiential means, educators can support interest development through structured reflection. Our randomized controlled intervention study assessed the effectiveness of 10-minute written utility-value reflections designed to enhance the interest of introductory animal science students. During the Spring 2019 semester, we randomly assigned participating students into two blocks, utility-value reflection (n = 39) and control (n = 34), at the beginning of the course. In week 6 during the 16-week semester, students completed corresponding tasks: either written reflections on the personal value of course laboratory material or a control picture-summarization task. Results showed that the utility-value reflection intervention tended to improve situational interest and was most effective for students with low pretest individual interest. Neither the intervention nor the interest variable predicted course performance. In utility-value reflection responses, we catalogued themes aligned with a range of task-value components beyond utility-value. Our results reinforce previous work indicating that utility-value reflections support low individual interest students in developing academic motivation.