This study is investigating the student-teachers' conception of static electricity in Rwandan teacher training colleges. The study used a pre- and post-intervention design, where two groups of students were randomly assigned in two groups. Along a period of four weeks, one group was taught using the traditional method (TRAD) while another using improvised experiment (IME) method. The student-teachers were given a test before teaching while after teaching the same test was administered to both groups. The study was not interested in testing student-teachers' achievement rather the conception of static electricity. The test was composed of six item questions and their answers were coded as "out of the topic, unrelated information and opposite answers". After performing pre-test, student-teachers showed confusions related to non-mastery of content and alternative conceptions related to static electricity and magnetism. Though about 27 per cent and 17 per cent of student-teachers in TRAD and IME respectively, reduced the gaps in their confusion after getting teaching intervention, however, there was found to be no statistically significant difference (p>0.05 at df=10) in all of the item questions between these teaching methods in favour of IME. Four item questions showed an improvement while student-teachers developed more conceptual confusions in other two item questions. Not only examining student-teachers' conception in static electricity but also teachers were recommended to be aware of students' ideas, opinions and confusions prior to their lesson planning, teaching materials preparation, as well as teaching implementation.