Inequality of educational opportunities and the role of learning intensity

Over the 2000s, many federal states in Germany shortened the duration of secondary school by one year while keeping the curriculum unchanged. The quasi-experimental variation arising from the staggered introduction of this reform allows me to identify the causal effect of increased learning intensity, the ratio of curricular content covered per year, on Inequality of Educational Opportunity (IEOp), the share in educational outcome variance explained by predetermined circumstances beyond a student's control. Findings show that higher learning intensity aggravated IEOp due to parental resources becoming more important through support opportunities like private tuition, adapting to an intensified educational process. The effect is stronger for mathematics/science than for reading, implying the existence of subject-dependent curricular flexibilities. My findings underscore the importance of accounting for distributional consequences when evaluating reforms aimed at increasing educational efficiency and point to the role of learning intensity for explaining changes in educational opportunities influencing social mobility.