Dissertation (MA Education)This study investigated the influence of teacher‟s knowledge and skills on Competence Based Assessment (CBA) practices on students' achievement in Commerce. The study also investigates teacher‟ assessment, behavior as well as to propose the best ways commerce could be taught following CBA. The sampled schools were seven. The study was a mixed research approach that used samples of 74 respondents; 7 academic masters, 13 Commerce teachers and 54 commerce students. Data were collected through questionnaires, interviews, Focus Group Discussion (FGD) and documentary analysis. Quantitative data were analyzed using Statistical Package for Social Science (SPSS) version 20 while the qualitative data were analyzed by organizing themes accordingly. The study found that the main teacher‟s knowledge and skills in CBA practices include assigning student different activities at the end of the lesson, the ability to assess subject competence and the provision of feedback to students on provided activities. The identified teacher assessment, behavior includes assessment of students at the end of the lesson, use of homework assignments and use test, quiz, and examinations as the major means of assessment. Finally, the proposed best ways Commerce could be taught following CBA include the use of teaching aids and supportive language to strengthen learning and to assign students different activities (hands-on and minds-on activities) during and after teaching and learning. The study concluded that the majority of teachers possess a partial knowledge and skills required in CBA practices in Commerce teaching and learning. It is recommended that In-service training to teachers about CBA should be done in order to equip them with proper and clear framework about CBA as the majority of teachers seem to lack adequate knowledge and skills regarding CBA.