The purpose of this study was to investigate the journey through the science project entitled "Super-Cool 3-D stereoscopic mirror" designed and produced by four primary students. Data were collected by field notes written from on-the-spot observations, the transcripts taken from the interviews as well as the dialogue among the teacher and students, students' journals, recording on the lab sheets, final project and other documents. Findings showed that: (1)during the initial observational stage, the students integrated prior experience by taking the problem as the central part for investigation, creating the purposeful learning cycle model, and developing a miniature of scientific community; (2)during the investigation stage, the students developed the final research questions via the frequent cross-checks by the "question organizers". The cross-type thinking model provided the strategies for solving problems and the foundation for extra-curricular learning; (3)during the data analysis stage, the students exerted their efforts to describe precisely with words, charts, symbols, and the interpretation for the images through red/blue glasses interlocking function which influenced the parallax. However, the principles as well as the conclusions of stereoscopic phenomena were inducted from the so-called "context-free" experimental activities. The exploratory journey showed that the four students could operate the higher-order thinking skills, such as the induction and problem-solving skills, and then actively constructed the investigation procedures based on the "learner-centered" rationale. The study not only demonstrated the educational meaning for science fair, but also could provide a reference for children's multi-dimensional development.