Many factors contribute to the performance of students in any given subject. The performance in mathematics and science subjects has been of great concern to the leaders in Kenya, who peg economic growth to the scientific development. In this country, the determining factor for success of a child in school is the performance in the national examinations which are administered by a semi-autonomous government agency and other professional bodies. The poor performance in mathematics and science examinations has generated debates nationally. This led to the introduction of many innitiatives to improve performance in these areas. One of this initiatives is Strenghtening Mathematics and Science in Secondary Education (SMASSE) for teacher in-servicing. It was envisaged that the SMASSE training would arm the teacher with a better pedagogical skills, develop interest in the students and change the perception towards this subjects and in particular Physics. This book discusses the results of Kenya Certificate of Secondary Education (KCSE) in Physics in Meru South District before and after the teachers were trained.