In this study we try to demonstrate that educational psychology can be constructed as a pedagogical science, integrated in the field of science education belonging to science education or science teacher. The expression "science education", well-known in literature in Britain and the U.S., is equivalent to "pedagogical science" used in other cultural spaces (We believe that our approach is necessary because most studies and books within the field treat, appreciate, educational psychology only a psychological science. This situation demonstrates that research in educational psychology is initiated, developed and finalized from a predominantly or exclusively psychological perspective. The trend is valid when the investigations are carried out by teachers.