Over many years of research, a decline in interest over the school years is repeatedly described. To address this decline, the value of content or a specific subject should be promoted. To increase content relevance, task value interventions can be conducted which are related to the theory of subjective task values by Wigfield & Eccles (2020). These values consist of intrinsic, attainment, and utility value. Due to its constructivist character, interdisciplinary interventions may meet preconditions to promote interest and could initiate situational interest and influence subject-specific values (e.g., utility value). The present study investigates whether and to what extent interdisciplinary interventions in biology and physical education influence the development of interest. A total of 73 students (mean age = 17.7 years) from four secondary schools took part in a one-day interdisciplinary intervention called "learning through movement," which combined physical education and biology. The intervention was accompanied by a modified quantitative questionnaire based on predescribed subjective task values. Mixed ANOVAs with repeated measures showed that the interdisciplinary intervention positively influenced situational intrinsic and utility values for both physical education and biology. By examining potential interaction effects, it was found that students with a low initial situational interest were positively affected by the intervention. Our study supports the notion that interdisciplinary interventions have an impact on subjective task values in biology and physical education and therefore have the potential to influence interest development, especially for lower interested students.