The study deals with the key psychodidactic topic – the optimization of mediation in educative process using the knowledge on intelligence, cognition and processing of information in the form of mental representations. In the presented study, the optimization strategy is mental mapping applied to educative processes in primary education in the field of language and communication and nature and society. The subject of the study is to identify the impact of mental mapping strategy on pupils' learning performance. The learning performance is operationalised at the factual, conceptual and procedural knowledge level and the study design is based on a pedagogical experiment. The results of the study indicate that the pupils reach higher level of learning performance when the mental mapping strategy is applied in educative process.