The importance of lighting for performance in human adults is well established. However, evidence on the extent to which lighting affects the school performance of young children is sparse. This paper evaluates the effect of lighting conditions (with vertical illuminances between 350 lux and 1000 lux and correlated colour temperatures between 3000 and 12 000 K) on the concentration of elementary school children in three experiments. In the first two experiments, a flexible and dynamic lighting system is used in quasi-experimental field studies using data from 89 pupils from two schools (Study 1) and 37 pupils from two classrooms (Study 2). The third experiment evaluated two lighting settings within a school-simulating, windowless laboratory setting (n = 55). The results indicate a positive influence of the lighting system on pupils’ concentration. The findings underline the importance of lighting for learning. Several suggestions are made for further research.