The main goal of this study was to investigate the influence of an established school programme with a high amount of physical education on visual-spatial ability in a secondary school. One hundred and forty-four adolescents, 69 from sport classes and 75 from regular classes, solved a cognitive processing speed task and a mental rotation task. The results reflect a better cognitive processing speed of the boys in the sports classes compared to regular classes but no differences for girls. Concerning the mental rotation performance, we found a significantly better mental rotation performance for boys and girls in the sports classes compared to regular classes due to an increased number of items worked on. Supposedly, motor expertise facilitates mental rotation performance by promoting a faster editing of the task. The benefits of sport classes in normal high school settings have to be investigated in further studies considering the effect on academic performance.