Students' school success in literacy and numeracy is often hampered by limited prerequisites in these domains, yet the effectiveness of different approaches to support students is unclear. Using professional training programmes for kindergarten teachers, we tested the effects of three kindergarten approaches in a quasi-experimental pre- and post-test-control-group design: (1) the "Pyramid Approach"; (2) a domain-specific training programme focusing on literacy and numeracy; and (3) a domain-specific Developmentally Appropriate Approach focusing on literacy and numeracy. A control group without any professional training for teachers and therefore without explicit domain-specific support for the children was also tested. Twenty-five kindergartens in Germany with 397 children between 5 and 6 years of age participated. The three intervention groups performed significantly better in terms of achievement in literacy and numeracy than the control group did, but there were no significant effects between the three intervention groups.