Idea generation in interactive learning environments requires the consideration of the interactivity and materiality aspects of creativity. In educational robotics, idea generation is mediated through a technological object in a process allowing us to observe the three main components of divergent thinking: fluency, flexibility, and originality. Nevertheless, divergent thinking assessment has been mainly evaluated in the last decades through semantic idea generation tasks such the Alternative Uses Test (AUT), asking participants to write different uses for familiar objects. In our study, we aimed to analyze differences in the three divergent thinking components (fluency, flexibility, and originality) through the AUT as a semantic task and through an educational robotic task that engaged the participants in building their ideas interactively. Results show that the creative components are strongly correlated within but not between the two tasks, leading us to consider the differences in the creative processes engaged when generating ideas through building with robotic objects. The role of affordances in idea generation through educational robotics is discussed as an important difference to consider in the evaluation of creativity in interactive learning environments.