Prior research has shown that greatest student achievement in sciences is attributed to "inquiry-based instructional approach", in which the goal of science teaching is nurturing attitudes and skills necessary for independent quest for scientific knowledge. While prior research has clearly demonstrated positive instructional effects of inquiry-based approach, there is little understanding of what factors determine utilization of the instructional methodology in classrooms. This study uses hierarchal-linear statistical analysis to explore the effect of some teacher, school and country-level factors that might determine utilization of inquiry-based approach around the world. Country level data for the study came from RAND's ranking of countries in terms of their science and technology capacity and the GDP data by the International Monetary Fund. Teacher and school level data were obtained from the international database for Trends in International Mathematics and Science Study 2007. Based on the results of intraclass correlation analysis, the study revealed that most of the variability is determined at the school level and, in addition, some slight variability is explained by differences among countries. The exploratory analysis was able to identify potential predictors at the individual level. None of the explored predictors at the school and country level were significant.