The empirical data in this study are from a series of two lessons on measurement implemented in seven classes with 119 six-year-old students in Sweden. Both problem solving and problem posing were shown to be important in early mathematics when students in this study worked on one problem-solving task and one problem-posing task on measurement. As there are few studies specifically on problem posing in early mathematics and on young children's understanding of measurement, this study adds knowledge of value for both teachers and researchers. In the study, paper-and-pen work from the students was analysed together with interviews conducted after the students had worked on the two tasks. When solving the task on measurement, the students discerned shape, size, distance, and number as mathematical aspects of measurement. When asked to pose a similar task, only size and number reoccurred as mathematical aspects of measurement. However, other features from the problem-solving task reoccurred in the posed tasks: similar drawings were used in combination with questions on measurement as the mathematical content.