The paper is focused on the investigation of impact of created experimental natural scientific programme for preschool-age children. Our programme concentrates on physics teaching adapted for preschool age in which children have possibilities to make experiments themselves--empirical cognition. Its innovation with respect to other stimulation programmes implemented in the past consists of including connection and thus developing a wide spectrum of intellectual abilities. Primarily, we are focusing on the impact of stimulation programme research on selected psychological variables, specifically intellectual abilities-intellectual maturity. Its second aim is to compare and test the validity of drawing tests designed for intellectual-level investigation of preschool-age children, school maturity, and school readiness. The obtained results do not provide evidence in support of the stimulation programme on developing intellectual/conceptual maturity. The results of the second part of the research (i.e., drawing) shows that the indicative level of intellect, perception, and motor maturity are closely related.