Venn Diagrams Tasks for Concept Formation in the Elementary School

Opportunities to use Venn diagram tasks for concept formation in elementary school are presented. The results of solving such tasks by students in 3rd and in 4th grade in the online competition "VIVA Mathematics with a computer" organized by the Institute of Mathematics and Informatics of the Bulgarian Academy of Sciences were analyzed. An illustration was made with similar tasks from other subject areas, inverse tasks were discussed, the role of computer models for their compilation and the competitions for their distribution.