Background/Objectives: The aim of the study was to evaluate the prevalence of undiagnosed hearing impairment or central auditory processing disorders in children from I and VIII grades of primary schools in Warsaw. Methods: The participants in the study were 15,659 pupils from classes I and VIII attending primary schools in Warsaw. As part of the study, the hearing threshold for air conduction at frequencies of 0.5–8 kHz was determined, and a test assessing central auditory processing was performed: FPT (Frequency Pattern Test), DDT (Dichotic Digit Test), the Auditory Behaviour Scale (SAB), and an interview questionnaire developed for the program. Results: Abnormal test results were found in 1946 children, of which abnormal hearing screening test results were found in 678 children tested, while reduced central auditory processing results were found in 1268 children. Conclusions: The program implemented draws attention to the fact that tests of central auditory processing are included in the testing protocol. As has been shown, peripheral hearing testing alone is not sufficient to exclude abnormalities concerning the sense of hearing.