Educational research maintains that, teaching science through designing technology has significant educational potential. Although the literature emphasizes that making technological designs is beneficial for students, it is stressed that studies about technological design generally focus on mental structures rather than hand skills of students and learning by doing and experience. In this study, we tried to determine the effect of a "Model Parachute Race" activity on elementary student teachers' levels of understanding of concepts such as air resistance, gravity, terminal velocity and acceleration using a qualitative methodology. In this context, elementary student teachers' levels of understanding of concepts were determined before and after the activity, and change was revealed through analyzing the difference between them. It was found that elementary student teachers learnt science concepts better during technological design process than during traditional science lessons. In addition, it is thought that if a technological design process is supported with theoretical information, desired change will occur in levels of understanding the science concepts.