Investigating the associations between student and school related factors and standardized test scores are important for researchers and policy-makers to ensure the social and economical well-being of the society. Given that, a vast majority of such studies have been conducted in developed countries, and their results are generalized to developing ones, which often leads to incorrect conclusions. The purpose of this book is to explore the effects of selected student and school level factors on 15-year-old students scientific literacy achievement in a developing country, Turkey. Thus, it helps researchers and policy-makers understand how the relationships between many exploratory factors and scientific literacy can differ from country to country.