The teacher participants selected content knowledge and level of students to be included in lesson plan. A content of electricity for Grade 6 students was chosen to be a content of interest to create inquiry-based science lesson plan using Lesson Study Process because it was hard to teach students to understand about electricity. The students had problems in answering test items about electricity. Their learning achievement about electricity was low both at school and national levels. All 6 teachers teach at Grade 6 level. Three topics of electricity were simple electrical circuits, symbol of electrical circuits, and electrical conductors and insulators. Each topic for each lesson plan was used to teach for 1 hour of teaching period.