This research examined how the C3 inquiry arc jointly improve learning abilities, learning motivation to social studies among sixth graders. This study had a quasi-experimental design in which quantitative data were primarily collected and analyzed, and qualitative data were collected as supplementary information. Participants were four sixth-grade students in an elementary school in Tao Yuan City. Different teaching activities were implemented for the treatment and control groups for a total of 9 lessons. Statistical analysis was performed on the data collected through the survey "learning for mid-term and final exams," the ARCS Learning Motivation Scale. In addition, the contents of the C3 inquiry arc course discussion sheet and worksheet were analyzed. The following research findings were obtained: (1) Students in both groups showed great progress in their academic performance, and no significant difference was observed. (2) In terms of learning motivation, the C3 inquiry arc course design improved the four aspects of in-class performance, namely attention, relevance, confidence, and satisfaction.