Despite their successful use in many conscientious studies involving outdoor learning applications, mobile learning systems still have certain limitations. For instance, because students cannot obtain real-time, context-aware content in outdoor locations such as historical sites, endangered animal habitats, and geological landscapes, they are unable to search, collect, share, and edit information by using information technology. To address such concerns, this work proposes an environment of ubiquitous learning with educational resources (EULER) based on radio frequency identification (RFID), augmented reality (AR), the Internet, ubiquitous computing, embedded systems, and database technologies. EULER helps teachers deliver lessons on site and cultivate student competency in adopting information technology to improve learning. To evaluate its effectiveness, we used the proposed EULER for natural science learning at the Guandu Nature Park in Taiwan. The participants were elementary school teachers and students. The analytical results revealed that the proposed EULER improves student learning. Moreover, the largely positive feedback from a post-study survey confirms the effectiveness of EULER in supporting outdoor learning and its ability to attract the interest of students. (Contains 7 figures and 9 tables.)