The aim of the current study is to develop a detailed understanding of how thirdgrade primary school students construct 3D printers in their minds based on their initial knowledge about 3D printers. This study, which was conducted with a phenomenological design, is one of the qualitative research methods. The participants of the study consisted of 52 third-grade students who were selected through a criterion sampling method. The implementation phase of the research was planned as two lesson hours. Data was gathered via semi-structured student interview form, semi-structured teacher interview form and unstructured researcher observation notes. The results of the research showed that participants have a high interest in 3D printers. Besides, it was found that the participants were willing to obtain detailed information about 3D printers. In addition, it was concluded that although students had a limited understanding of the usage areas of 3D printers, they could associate them with education.