Because of time limits, the unit ”Moon Observation” of Science and Technology could not be finished during the planned schedule, and thus fourth-grade students’ knowledge of this subject was incomplete. The purpose of research is to remedy the deficiency of students’ knowledge and then develop learning strategies. The researcher used classroom discussion of non-direct teaching methods as a remedying activity. In the open teaching activity, through classroom interaction and experience exchange among students, students and the teacher, several innovative ideas and concepts emerged. The researcher used the observation and interview method to collect data. At the end of the activity, the researcher integrated students’ ideas to develop new learning methods by analysis as follows: 1) using gestures to check the phase of the moon; 2) using gestures to check the position of the moon and 3) using gestures to check the first and third quarter of the moon. These methods can be an auxiliary tool for future study and are convenient and effective for moon observation. Further, use of such methods can help students to have ability of observation in their own life.