This study reported how four science teachers used action research to promote their students' motivation in learning physical science. Four teachers with one of their 8th grade physical science classes participated in the study. A combination of qualitative and quantitative research design were used in the study, and data collection included Students' Motivation toward Science Learning (SMTSL) questionnaire surveyed in the beginning, middle and at the end of the study, interview with students and teachers, and classroom observation. Findings of the study indicated that four teachers had their preference teaching methods in promoting their students' motivation. However, they still shared common teaching activities which included having lab activities, making science relevant to the experiences of students' daily lives, providing opportunities for students to work and discuss together, giving more praise for students' good effort, and accepting students' responses without criticizing them. Toward the end of the study, students' scores showed a significant difference (p<.05) between pre- and post-tests on SMTSL, particularly on self-efficacy and achievement goal scales. The study concludes that, although the content covered in 8th grader's physical science class became more abstract and difficult, teachers can still promote students' motivation in science learning with long periods of improving teaching effort. (Author)