The poor state of learning in pre-service science teacher education is typical of the problems in the Nigeria education sector. Little research based evidence about Nigerian pre-service science teacher education has been reported in the literature. This thesis reports a case study of the quality of a pre-service science teacher education programme in a Nigerian College of Education and the graduate teachers'' transition to science teaching in Lagos State, Nigeria. The research involved both qualitative and quantitative methods. Quantitative data were sourced from questionnaires completed by third-year Nigeria Certificate of Education (NCE) students and first-year Junior Secondary School (JSS) science teachers. Qualitative data were obtained from focus group meetings with science and education lecturers, third-year NCE students and first-year JSS science teachers. Interviews were conducted with major key stakeholders in JSS education in Lagos State, Nigeria. Triangulation of data sources enabled the Researcher to corroborate findings thus ensuring the credibility and trustworthiness of the conclusions to the study.