Epidemiological data reveal that there is a need for prevention measures specifically targeted at children with low SES. In the German federal state Mecklenburg-Western Pomerania preschools in socially deprived regions can apply for additional funds to support children with developmental risks. Mandatory criteria for obtaining these funds involve an annual assessment of all children using the Dortmunder Developmental Screening for Preschools (DESK 3-6 R). This instrument can detect and monitor developmental risks in the domains fine motor skills, gross motor skills, language, cognition, and social development. In this study, we examine the domain Attention and concentration, which is included for the 5 to 6-year-old age group, using data from two consecutive survey waves (sw). Research questions: (1) Does the prevalence rate ratio (PRR) improve over time? (2) Is the rate of improvements (developmental risk at sw1, no developmental risk at sw2) higher than the rate of deteriorations (no developmental risk at sw1, developmental risk at sw2)? Prospective cohort analysis (n = 940). The prevalence rate of a developmental risk in this DESK domain decreases over time (PRR = 0.78; p = 0.019). The ratio of the rate of improvements is 8.47 times higher than the rate of deteriorations. The results provide evidence of the effectiveness of targeted intervention measures in preschools focusing on skills that improve attention and concentration. This is significant considering the small-time interval and the categorization method of DESK scores. Nevertheless, over the same time period, the DESK results of some children deteriorated. Therefore, preschools also have to be aware that it is natural for some children to show modest declines in their skills over time. German Clinical Trials Register, ID: DRKS00015134, Registered on 29 October 2018, retrospectively registered.