This study was to analysis the changes of technology concepts for those who were involved in water-saving innovation contest. Through interviews and qualitative analysis, researchers understand the participants' water-saving technology concepts and their changes through different activities. Elementary students and their parents formed as a group to conduct the innovative design for water-saving device. Using purposive sampling, researchers interview 4 groups and take 11 interviews and analysis their video files, design plans and other documentary sources as cross-exam to find their technology changes. The results show that the water-saving contest do changes the participants' technology concepts.