In order to initiate more research on the role of reading motivation during the initial stages of learning to comprehend texts, we developed the "Reading Motivation Questionnaire for Elementary Students" (RMQ-E). The sample comprised 1497 elementary students in Grades 1-3. By means of exploratory and confirmatory factor analyses, three factors were determined: Curiosity, involvement and competition. The three-factor structure of the RMQ-E was found to be invariant across grade levels (scalar invariance) and across female and male students (strict invariance). As was anticipated, students in higher grades and male students were lower in curiosity and involvement than students in lower grades and female students. Whereas competitive reading motivation did not differ across grade levels, it was higher for boys than for girls. Moreover, the contributions of involvement and competition to reading amount and reading competence were in accordance with the hypotheses. The predictive validity of curiosity, however, was not confirmed.