Education should ensure that all children can move safely in the digital world, understand the phenomena and be able to play an active and self-determined role in shaping the future. A positive informatics-based self-concept (i.e. a self-concept regarding topics of informatics in school) is an important step towards this goal. In this study the informatics-based self-concept of primary school children is compared between children who had informatics1 lessons and children who did not. This study introduces a questionnaire that measures the informatics-based self-concept, which was filled out between May and June 2019 by primary school children from a project group (262 children) for informatics in the 3rd and 4th grade and a similar control group (61 children) without informatics. Results indicate that both groups have a rather high positive informatics-based self-concept, but that the children from the project group rated themselves more positively than the control group in all dimensions. The analysis of the gender-related differences revealed that the informatics lessons seemed unable to compensate for gender-related differences in self-concept. In detail, the girls in the project group assessed themselves lower in self-concept than the boys, whereas the boys and girls in the control group did not differ statistically significantly regarding their self-concept.