The development of and interplay between secondary school students' individual interests and achievement were investigated using the example of chemistry education. In a two-cohort study with yearly measurement occasions (Grade 6–8, N = 580, Mage = 11.6 years in Grade 6; Grade 9–11; N = 473, Mage = 14.7 years in Grade 9), we assessed both students' domain-specific and activity-related interests. While measurement invariance could not be established for students' domain-specific interest, results based on multi-group latent change score modeling indicate a rather stable pattern of cross-lagged effects between activity-related interests and achievement within and across cohorts. Significant cross-effects were only found for interests in activities that imply a closer association to cognitive activation and communication of knowledge. These findings extend research pertaining to the longitudinal interplay between interest and achievement and indicate the opportunity to counteract the often reported decline of interest, especially in STEM subjects.