This chapter presents the issue of education and skill inequality in sociology and economics. This will be followed by a brief explanation of skill-biased technical change (SBTC) and human capital externalities in urban areas where educational-related inequality is a major issue and is usually associated with other socio-economic problems. The chapter discusses educational assessment, comparison and the Science, technology, engineering and mathematics (STEM) subjects as cultivators of the “right” kinds of skills in terms of their abilities to decrease educational inequalities from the perspectives of sociology and economics. In economics, the issue of inequality in education and skills refers to the distribution of schooling achievements and skill levels among the adult population. SBTC represents one of the main explanations provided by the economic literature dealing with the wage inequality and job polarization that have been observed in developed countries since the 1970s.