This study explores how theoretical elements of design knowledge relate to notions of creativity found in literature. The results of this exploration are further applied to analyze four different cross-curricular design and technology projects in Norwegian primary and lower secondary school. All of the school projects examined were intended to be open-ended providing students with opportunities to be creative and develop their own solutions to the given task. The processes in the groups and the outcomes of the groups' work are analyzed with regards to technological knowledge and how this relates to the students' creativity in terms of producing genuine solutions. The analysis shows that in some of the projects the variety of solutions produced by students is limited. In these student groups the solutions and procedures bear a high degree of resemblance to each other. The findings further suggest that students' limited conceptual technological knowledge constrains their ability to be creative and to produce genuine solutions. The results also reveal that the projects showing less student creativity tend to be more controlled by the teacher and less open-ended than presupposed. A suggestion based on the findings is that the key conceptual technological content should be identified and introduced by the teacher prior to or during the project start. Discussing and exploring concepts and principles explicitly with the students before or during the project period may enhance their possibility to be more creative.