Educational robotics has been regarded as an effective instructional tool over the past decade. Many studies have tested the role of robots in supporting educational classroom activities. However, reliable empirical evidence confirming the effectiveness of educational robots remains limited. Therefore, this study developed an educational robot-based learning system that provides an attractive teaching application that combines multimedia objects with an educational robot. This study examined the impact of the proposed learning system on student learning performance and motivation. The four-stage experimental procedure involved a pre-test, post-test, learning activities, and questionnaire survey. The participants comprised one homeroom teacher and 52 second-grade students from two classes at an elementary school in Taiwan. All of the students were assigned to use either the proposed learning system or a PowerPoint-based learning system. The pre-test and post-test results show that the proposed learning system improved student performance more than the PowerPoint-based learning system did. A questionnaire based on the Instructional Materials Motivation Survey (IMMS) was employed to measure four motivational factors (attention, relevance, confidence, and satisfaction). The IMMS survey results show that satisfaction and relevance were the highest rated motivational factors among students who used the proposed learning system. The experimental results indicate that the students were motivated to use the educational robot-based learning system. Thus, using educational robot-based learning systems in classrooms demonstrates a significant advantage for students, by improving overall learning interest and motivation.