The aim of this study is to determine the effect of educational practices designed in experi- mental research on children’s problem solving skills for the children aged 3-6 years attending pre-school education. In this context, a total of 1012 master’s/doctorate theses, of which 321 with the original scans and 691 supplementary scans, were examined between 1987-2021 (Oc- tober) in Turkey. When the studies were examined according to the criteria, it was determined that 27 theses were suitable for meta-analysis.In the study, descriptive statistics data, publica- tion bias, heterogeneity and effect sizes were analyzed with the Comprehensive Meta-Analysis Version 2 program. It was concluded in the analyzes that there was no publication bias and that the effect sizes of the studies had a heterogeneous distribution.When the effect of experi- mental education practices on children’s problem solving skills was analyzed in the random effects model, it was found that the effect size value was in favor of the experimental group. The obtained value shows that the educational practices designed in the experimental research for children aged 3-6 in preschool education have a higher level of effect on children’s problem solving skills compared to the Cohen d classification. When the moderator analysis results are examined, for the overall effect size; while reaching the conclusions that the age group of the children and the type of preschool education institution they attend, the type of thesis study, the department and university in which the thesis was made, the year the thesis was made, was’nt moderator; The institute where the thesis was made was found as a moderator variable for the overall effect size.