Physically or visually represent thoughts on the topic. This can be carried on both by the designer and the child participants, together or separately. Materialising helps to mediate and make evident implicit understandings. The designer should make sure to leave space for the participants for them to freely express their perspectives.

• Build prototypes
• Visualise or map out emotions or ideas
• Free experimentation with a material
• Cooperative building

Such materialised outcomes can also be used for further testing and validating with either same or different participants, and depending on the age-group involved even engage a critical discussion around what has been done.