Computational modelling is widely used in biological science. Therefore, biology students need to learn computational modelling. However, there is a lack of evidence about how to teach computational modelling in biology and what the effects are on student learning. The purpose of this intervention-control study was to investigate how knowledge in computational modelling is associated with knowledge acquisition in biology. Participants were 118 students (17 to 19 years of age) enrolled in first and second year of Danish High School. The intervention group (n = 81) received teaching in biology and computational modelling while the comparison group (n = 37) received teaching in biology using textbook models. Both groups received two sessions, each of approximately 120 minutes. The study used mixed methods to analyse students' knowledge of biology and computational modelling. Participants in the intervention group showed statistically significant improvements in their biological knowledge and computational modelling knowledge. The study is one of the first to investigate the effect of computational modelling on high school students' learning of biology. The study discusses how biology could be an important subject where students can learn computing concepts central in the endeavour to introduce computing in high school education.