The purpose of this study is to use the matrix laser teaching aids to teach in the moon observation unit to explore the effectiveness of science learning of elementary school students. The subjects of the study were 367 fourth-grade students in an elementary school in New Taipei City, including 154 students in the experimental group and 213 students in the control group. In this study, we first designed a matrix laser teaching aids to produce parallel light like the sun, so as to provide moon observation unit for teaching, which can show the true changes of moon phase changes in teaching. Students in the experimental group received the instruction with the matrix laser teaching aids on the moon observation unit, while students in the control group received the conventional instruction. The research instrument is the Moon Observation Unit Achievement Test, and the reliability of the test is Cronbach [alpha]=0.72. The analysis of research data adopts covariate analysis. The results of the study found: (1) There is no significant difference between the experimental group and the control group in the learning effects on the concepts of the moon; (2) The experimental group did better than the control group on the understanding of observing the moon (F=10.211, p<0.01); (3) The experimental group did better than the control group on the understanding of moon phase changes (F=10.220, p<0.01).Therefore, it can be concluded that using matrix laser teaching aids is effectiveness for the moon observation unit in this study. [For the full proceedings, see ED623149.]