Anthropomorphized robots are regarded as beneficial tools in education due to their capabilities of improving teaching effectiveness and learning motivation. Therefore, one major trend of research, known as Robot- Assisted Language Learning (RALL), is trying to develop robots to support teaching and learning English as a foreign language (EFL). As more practical studies on materials development have been called for, this paper details the methods of adopting the proposed RALL framework to design robot-assisted instructional materials for elementary students studying in an EFL national curriculum in Taiwan. Quantitative and qualitative experiments were conducted in this research to investigate the learning performance and motivation of the designed robot-assisted instructional materials. Two groups of participants from an elementary school in Taiwan enrolled in this experiment. The post-test results revealed that the experimental group outperformed the control group, particularly in terms of the improvement of listening and reading skills. Furthermore, the motivation survey of the instructional materials also showed that the experimental group's learning motivation was positively influenced. Therefore, our research demonstrated that the instructional materials developed by our RALL framework provide a great opportunity to foster elementary students' English language learning.