The aim of this research was to design an inquiry-based mobile learning strategy that integrated the physical environment and digital resources to enhance elementary students' learning of historic monuments. The students were situated in both the real world and the virtual world to extend their learning experiences. Based on collaborative learning principles, students used the handheld device, PDA, to do their investigations. This research utilized the Peace Temple in Taiwan as the teaching and learning site and invited 32 fifth graders to participate in the learning activities. Through pre- and post-class questionnaires, as well as observations and focus group interviews, both qualitative and quantitative data about students' social relationships were collected and analyzed. The results showed that students' social relationships varied at different stages with different tasks. Inquiry-based mobile learning is shown to have positive effect on students' learning performances and learning satisfactions.