Elementary school remedial teaching has been promoted for many years in Taiwan but it has primarily been aimed at Chinese and mathematics with little attention being paid to natural sciences. Due to the current shortage of natural science teachers, along with limitations in school budget and manpower, it is difficult to put natural science remedial teaching into practice in elementary schools. This research attempts to establish a new model of remedial teaching that utilizes remote asynchronous video-based instruction to carry out centralized remedial teaching with 3D television and interactive response system. We focused on fourth graders whose science ranking was at the bottom quarter and examined if their grades have improved. Centralized remedial teaching was implemented once a week during school's noon break and lasted for 40 minutes. The materials used, including the remedial 3D natural science lesson videos and interactive response test questions, were both produced by the university. They were transmitted through the Internet to elementary school teachers who played them on 3D television and students practiced and answered the questions in real time with plickers. Twenty fourth graders from different classes participated in remedial teaching for one semester; the average percentage of test grade ranking in natural science has progressed from 9.19% to 24.12% in their original classes. Previously, the average of T-score in natural science test was 35.80, and after remedial instruction, the T-score average was 42.39. The T-score average improvement is statistically significant (t = 3.34, p = 0.003). The research revealed that this instructional model can improve learning outcome in natural science for underachieving fourth graders, and through the questionnaire, it was also known that the students liked this remedial teaching approach.