Problem posing is a promising teaching method and an important learning objective, but its conceptualization with reformulation and generation as two cognitive activities remains largely unclear. The aim of this study (N = 116 ninth and tenth graders) was to examine the structure of problem posing and its relationships with mathematical performance and creativity. Our results indicate that reformulation and generation are distinct problem-posing facets which are positively related to mathematical performance. Furthermore, the performance and originality of problem generation—but not problem reformulation—are positively correlated with creativity. These findings suggest that the reformulation and generation of problems may require different skills and have varying impacts on other constructs such as creativity.