Developing Secondary School Students’ Understanding on the Newton’s Third Law by Predict-Observe-Explain

This study aimed to develop students’ understanding of Newton’s third law of motion through the Predict-Observe-Explain teaching method. The target group was 69 Satri Sisuriyothai students: grade 11. The research instruments included a lesson-plan, a demonstration kit, a test. The data were analyzed by comparing understanding pre-test with post-test. The analyzed data showed that student’s misunderstanding in case of the massive object had more action force than the light object while resting, reduced from 100.0% to 13.0%, in case that both objects had the same speed crashing equal action force when they were crashing, reduced from 94.2% to 15.9%, and in case of the object which had more speed while crashing produced more action force, reduced from 100.0% to 7.2%. Moreover, the students who studied through Predict-Observe-Explain got a higher mean score at statistical significance .05 level. According to the results, the Predict-Observe-Explain teaching method and the demonstration kit can develop students’ understanding.